Announcement

Collapse
No announcement yet.

Intake Air Temperature Measurements and Studies

Collapse
This is a sticky topic.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Intake Air Temperature Measurements and Studies

    Many of our Forum members are aware of the linear relationship between intake air temperature and HP output. Considering only these two variables, HP varies essentially as the square root of the change in ABSOLUTE temperature. Because of this relationship, it becomes a matter of interest for anyone involved in the search for increased power output to determine the temperature of the intake charge. This applies to both NA and FI engines. For a more complete explanation, go to:
    http://www.wihandyman.com/forum/showthread.php?t=995

    Some time ago I installed a digital ambient air temperature gauge in my car with the sending unit mounted in the air box. This gives me the means to record intake air temperatures under varying operating conditions. The gauge is made by Cyberdyne and has a range of -22 to 158 deg F. Gauges are also available with SI readouts in a range of -30 to 70 deg C. For more details, check out:
    http://www.wihandyman.com/forum/showthread.php?t=47841

    This thread is intended to provide you with some of the observations I've been able to make and some of the conclusions I've drawn based on how intake air temperature varies as a function of different driving and ambient air temperature conditions.

    To begin, it's necessary to briefly describe the characteristics of my air intake system. It's a modified OEM system and the two salient features for the purposes of this discussion are that, (1) the inlet is located in a high pressure area sealed off from the engine compartment such that it ONLY ingests ambient temperature air, and (2) with the exception of the inlet, the entire system is sealed up to the air box accomplished by blocking the six drain holes located in the snorkel, the Helmholtz resonator and the air box, thus insuring no underhood temperature air can be drawn into the system. For a more complete description of my system, you can access the details at:
    http://www.wihandyman.com/forum/showthread.php?t=1977

    It's also worth noting that a digital temperature gauge responds much more rapidly to temperature changes than an analog instrument, as well its readout is precise requiring no interpolation as is often required in the case of the latter.

    Determining the Baseline Temperature
    It’s important to determine the baseline temperature in the air box before running a test so we’ll know how much variation takes place, but just how accurate is the baseline temperature? This depends on the ambient temperature and whether the car is parked in sun or shade. Below a certain temperature, the baseline can be considered the ambient if the car is dead cold. However, at higher temps and especially when parked in direct sunlight, heat absorption occurs under the hood (and in the air box) and even when starting from 'cold' the baseline is actually above the ambient. This is obvious when, after brief idling or placing the car into motion, the gauge reading falls to a level lower than the initial one. This factor has to be taken into account when making comparative temperature readings. That’s why, in the warmer weather, I always obtain a NWS temperature reading in the area from which the test will begin and use that as the baseline. Incidentally, at start-up, if the temperature read by the sensor is 37 degrees F or less, the gauge display flashes ICE for one minute and then returns to normal operation and displays the numeric temperature.

    Ideally, I’d like to have a second switchable sender to measure OAT but if the sender is mounted in the bumper per Cyberdyne’s recommendation, it too could be subject to heat soak. I’ve noticed in my wife’s 3 that in warm weather the OAT gauge reading also falls somewhat after the car is put into motion, before it stabilizes.

    We do what we can!

    Cruise, High-Speed and Highway Running
    As long as the vehicle remains in motion, the air box temperature seems to fairly closely track the ambient, remaining not too far above it. As speed increases to 40 mph air box temperature tends to decrease but there seems to be little, if any, temperature difference in the range between 40 and 85 mph in terms of change. At steady cruise on the Interstate between 60 and 85 mph for very long periods of time (assuming no change in the ambient), the gauge either holds steady or changes by no more than 1-2 deg F.

    Idling, Slow-Speed, In-Town, and Stop-and-Go Driving
    Here, the situation is completely different and illustrates the pronounced effect the driving mode has on temperature change. At slow speeds and especially at traffic light stops, the temperature rapidly climbs well above the ambient. The longer the stop, the higher the recorded temperature. Stop-and-Go driving has a similar effect. The higher the ambient and baseline temperatures to begin with, the more rapid the climb and the higher the end temperature. Idling produces both the most rapid rise in temperatures over time and yields the highest recorded temperatures. However, once a return to a more fluid driving mode is possible, the temperature fairly quickly falls to more normal levels.

    After Shutdown
    One interesting phenomenon I've observed is that after engine shutdown, the temperature in the air box climbs to levels much higher than were seen during actual running. Checking the air box temperature one hour after shutdown by restarting the engine, I typically find the gauge reads at least 30 deg F above that recorded at shutdown. Furthermore, after just parking the car for a few minutes, at restart the gauge reads significantly higher than it did at shutdown.

    Conclusion
    Based on the above observations, I think we can draw two conclusions. The first is that due to the air intake modifications, the system succeeded in providing a relatively cool intake charge to the engine as illustrated by the temperature gauge readings in which the air box temperature (remember, this is where the IAT sensor is situated) remained only slightly above the ambient in driving modes involving cruise, high speed and highway running.

    The second is the way in which heat absorption profoundly increases intake air temperatures during idling, slow-speed, in-town, and stop-and-go-driving.

    The Effect of Heat Absorption on Intake Air Temperature
    The way in which heat absorption markedly increases intake air temperatures in the induction system has been discussed by AEM. Unfortunately, for whatever reason AEM has removed this discussion from its website and the reference is no longer available. Nevertheless, because of its clear, easily understandable exposition of this factor, I’ll still include it here.

    Justifying their use of aluminum tubing over plastic even though aluminum is subject to greater heat soak, AEM asserts that the thermal conductivity of the duct material has little effect on engine power. Instead, the rate at which air travels through the intake duct under full throttle demand for maximum power negates the effect of material heat soak, regardless of the material. The article goes on to say that at small throttle openings (including idle), the air speed and airflow in the inlet system are relatively low. The high residence time of air in the inlet at low-throttle settings will increase inlet charge temperatures as heat is easily absorbed from the duct by the slow-moving air. However, when the throttle is fully opened, airspeed and air flow increase considerably. Now, the rapidly moving air has little opportunity to take on heat from the surrounding duct and the intake charge temperature drops.

    Further confirmation that idle and slow-speed running increases intake air temperature due to the fact that, under these conditions, the slower moving air has more opportunity to pick up heat as it traverses the intake duct and manifold, is provided by Pulkrabek. According to the author, "All intake systems are hotter than the surrounding air temperature and will consequently heat the incoming air. This lowers the density of the air, which reduces volumetric efficiency. ... At lower engine speeds, the air flow rate is slower and the air remains in the intake system for a longer time. It thus gets heated to higher temperatures at low speeds, which lowers the volumetric efficiency curve at the low-speed end."
    Reference:
    Engineering Fundamentals of the Internal Combustion Engine, Second Edition, by Willard W. Pulkrabek; Chapter 5: Air and Fuel Induction, Section 5.2, page 193.

    From this point I intend to post actual temperature readings as a function of various driving modes, routes and ambient temperatures to give a clearer picture of how these elements are interwoven together and related to intake air temperatures.

    I look forward to your comments, additions and suggestions. Please remember, I'm not touting my intake system as the best or denigrating anyone else's efforts. My system is the best for me and the kind of driving I do - only this and nothing more.

    Happy Motoring!
    Last edited by goldstar; 05-03-2010, 09:36 AM.
    02 DX Millenium Red - The Penultimate Driving Machine
    MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
    MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
    Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
    MP3 Shifter, Knob and Aluminum Pedal Set
    Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
    Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
    Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
    Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
    Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
    Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
    Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
    Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

    #2
    Test Mission No. 1 (January 2007)

    This was a ride to no particular place designed to give me familiarity with observing and recording temperature data while driving.

    Route, Driving Modes and Temperatures (23 mile course)
    1. Startup (baseline) temperature: 37 deg F (3 deg C).

    2. After 3 miles of intown and suburban running between origin and I-287: 45 deg F (7 deg C).

    3. After 5 miles of interstate (65-80 MPH), and 12 miles of 2-lane suburban and rural highway running (fairly constant 40 MPH, no traffic light stops): 42 deg F (6 deg C).

    4. After 3-miles of suburban and intown running from end of step 3 back to point of origin: 46 deg F (8 deg C).

    Results
    Maximum temperature differential between baseline and constant running mode: 42-37 = 5 deg F (278.71-275.93 = 2.78 K). Percentage rise over baseline temperature = 1%.

    Maximum temperature differential between baseline and all modes combined: 46-37 = 9 deg F (280.93-275.93 = 5.00 K). Percentage rise over baseline temperature = 1.8%.

    Immediately after engine shutdown, the hood was opened and a qualitative digital test was performed. Results: top of snorkel and interior of inlet as far as my digital probes could reach-cold. Bottom of snorkel (located over radiator)-slightly warm. Helmholtz resonator, air box, MAF sensor housing and rubber connecting hose-cold. TB-very warm to hot depending on individual neural sensitivity.

    Conclusion
    System seems very effective at maintaining intake air temperature in air box at close to the ambient (at least in the absence of traffic and when the ambient is in the 30-degree range).

    Note that in the results above, as well as providing the numerical increase, I have calculated the percentage increase of the maximum temperature observed over that of the baseline. In order to obtain this figure it’s necessary to convert the Fahrenheit or Celsius temperature scales to the Kelvin absolute temperature scale. The F and C scales are interval scales with an equal interval between scale points but where the zero point of either scale does not coincide with the absence, or starting point, of the property being measured. The Kelvin (or the Rankine) is a ratio scale, in which the zero and origin points coincide, enabling ratios, proportions, or percentages to be calculated between scale points. Consequently the percentage change figures are derived from the Kelvin scale. To accomplish this, it’s only necessary to convert F to C to K and then perform the required computation. To convert C to K, add 273.15 to C. This is the method I’ll follow in all subsequent posts in this thread.

    Happy Motoring!
    Last edited by goldstar; 05-01-2010, 06:57 AM.
    02 DX Millenium Red - The Penultimate Driving Machine
    MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
    MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
    Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
    MP3 Shifter, Knob and Aluminum Pedal Set
    Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
    Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
    Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
    Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
    Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
    Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
    Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
    Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

    Comment


      #3
      Test Mission No. 2 (February 2007)

      Another familiarization run with no particular destination.

      Route, Driving Modes and Temperatures (29 mile course)
      1. Startup (baseline) temperature: 19 deg F (-7 deg C).

      2. After 3-miles of intown and suburban running between origin and I-287: 21 deg F (-6 deg C).

      3. After 5-miles of interstate running (fairly constant 75 MPH cruise): 23 deg F (-5 deg C)

      4. After 10-miles of multi-lane state highway running (max 60 MPH): 26 deg F (-3 deg C). Two brief traffic light stops at which time temperature
      climbed to 28 deg F (-2 deg C), but max running temperature was 26 deg F.

      5. After 8-miles of 2-lane suburban and rural highway running (fairly constant 40 MPH, no traffic light stops): 26 deg F (-3 deg C).

      6. After 3 miles of suburban and intown running from end of step 5 back to point of origin: 26 deg F (-3 deg C).

      Results
      Maximum running temperature differential between baseline and all driving modes combined: 26-19 = 7 deg F (269.82-265.93 = 3.89 K). Percentage rise over baseline temperature = 1.5%.

      Immediately after engine shutdown, the hood was opened and a qualitative digital test was performed. Results: top of snorkel and interior of inlet as far as my digital probes could be inserted-cold. Bottom of snorkel (located over radiator)-cool. Helmholtz resonator, air box, MAF sensor housing and rubber connecting hose-cold. TB-slightly warm.

      Conclusion
      Smallest spread yet obtained between baseline temperature and maximum running temperature. Evidently, the lower the ambient temperature, the smaller the measured differential.


      Happy Motoring!
      02 DX Millenium Red - The Penultimate Driving Machine
      MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
      MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
      Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
      MP3 Shifter, Knob and Aluminum Pedal Set
      Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
      Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
      Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
      Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
      Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
      Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
      Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
      Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

      Comment


        #4
        Unplanned Test: Unexpected Results

        On Friday evening, 2/09/07, I drove to a friend's house located ~ 20 miles from my home. I started my trip at 6 pm and the ambient temperature according to the NWS was in the 20s F. As this wasn't a test mission, I didn't note or record the starting or baseline temperature. The Interstate is close to my house and after a couple of miles cruising on it at 70 mph (traffic was somewhat heavy, but moving), I happened to note that my air temperature gauge read 29 deg F (-2 deg C). At some point, I turned off the Interstate and onto a heavily traveled state highway (it was the tail end of rush hour and a Friday night). A glance at the air temperature gauge showed it reading 31 deg F.

        Almost immediately after reaching the highway, I ran into a massive traffic jam. The stretch of road I was on contained three lanes and somewhere up ahead (as I later learned) two lanes were closed off forcing all traffic into one lane for a short stretch. I was now in bumper-to-bumper, stop and go, 1st gear traffic, and I crawled along in this condition for ~ 15 minutes until I cleared the blockage. Having little else to do, I kept an eye on the air temperature gauge and watched its steady upward climb. When I was finally able to get free of the jam, the temperature gauge read 116 deg F (47 deg C)! A pretty impressive climb given the then ambient temperature.

        For the remainder of my trip, ~ 8 miles, I was able to run in a more normal speed range of 45-60 mph during which time the temperature dropped to 36 deg F (2 deg C).

        Results
        Maximum temperature differential: 116-29 = 87 deg F (319.82-271.48 = 48.34 K). Percentage rise over lowest observed temperature = 17.8%.

        Conclusion
        Considering the ambient temperature, I was surprised that the temperature climbed as high as it did. Also, I have no idea whether the temperature would have continued to climb, and to what point, had I been in the traffic jam for an even longer time. It will be interesting to see what happens in similar situations in Summer temperature conditions.


        Happy Motoring!
        02 DX Millenium Red - The Penultimate Driving Machine
        MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
        MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
        Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
        MP3 Shifter, Knob and Aluminum Pedal Set
        Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
        Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
        Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
        Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
        Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
        Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
        Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
        Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

        Comment


          #5
          Test Mission No. 3 (March 2007)

          I had to drive to an engineering company located 73 miles from my home. This was job related and since it was an extremely cold day for this region, I decided to incorporate a test mission into the trip. This differs from Test Mission No. 2 mainly in the length of the trip, making it possible to see if that's a factor in maximum temperature attained.

          Route, Driving Modes and Temperature Readings (73 mile course)
          1. Startup (baseline) temperature: 28 deg F (-2 deg C).

          2. After 3-miles of intown and suburban running between origin and I-287: 26 deg F (-3 deg C).

          3. After 22 miles of interstate running on I-287 to entrance to I-87 (65 to 80 MPH cruise): 25 deg F (-4 deg C).

          4. After 34 miles of interstate running on I-87 to point of exit (fairly constant 75 MPH cruise): 25 deg F with occasional excursions to 26 deg F and then back to 25 deg F.

          5. After 14 miles of 2-lane state highway running in a rural area to destination: 30 deg F (-1 deg C).

          Results
          Maximum running temperature differential between baseline and lowest temperature observed: 28-25 = 3 deg F (270.93-269.26 = 1.67K); between highest temperature observed and baseline: 30-28 = 2 deg F (272.04-270.93 = 1.11K). Since the differences are so small, 3 and 2 degs F respectively, I didn't bother to calculate a percentage decrease or increase.

          Conclusion and Discussion
          Two conclusions are immediately apparent. First, unlike the previous tests, the running temperature decreased between baseline and sustained run on the interstate (28 to 25) instead of the usual increase. The most likely cause is that the ambient temperature decreased slightly as I proceeded farther north resulting in a decrease in air box temperature. The temperature rose above baseline in the running mode (28 to 30) only during the last leg of the trip after exiting the interstate.The temperature differential is the smallest yet seen.

          Second, the length of the run seems not to have an effect on temperature change assuming the engine and bay have reached operating temperature, the ambient temperature remains relatively stable and the vehicle remains in motion. Thus, the temperature stabilized at 25 deg F shortly after entering I-287 (~ 4 miles from origin) and remained at that figure 56 miles later when exiting I-87.

          Although you folks who live in the Southland with generally milder climates probably rarely experience this, we tougher folk who live in the cold north during winter are well aware that as the temperature drops, power, and consequently performance, increases noticeably. This is even more evident for our Canadian members.

          Since, in this test, there is a 52 degree F (28.89 K) difference between SAE standard temperature and the observed running temperature, I thought it would be interesting to post the increased HP figure generated by this difference. This new HP figure can be calculated using simple arithmetic to multiply the rated HP by the square root of the change in absolute temperature or obtained by an online calculator. Given that the 2.0 L FS-DE engine develops 130 HP SAE net, at 77 deg F (25 deg C), then at 25 deg F (-4 deg C) it should be outputting an additional 6.8 HP for a total of 137 HP. Not bad for 'free' HP and coupled with the modest boost I've obtained from my simple, backyard attainable mods, my car feels really good at these low temperatures.

          Correspondingly, in hot weather the performance decrement is all too noticeable.


          Happy Motoring!
          Last edited by goldstar; 05-01-2010, 06:48 AM.
          02 DX Millenium Red - The Penultimate Driving Machine
          MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
          MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
          Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
          MP3 Shifter, Knob and Aluminum Pedal Set
          Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
          Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
          Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
          Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
          Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
          Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
          Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
          Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

          Comment


            #6
            Test Mission No. 4 (July 2007)

            This involved a trip to a relative's house in Torrington, CT located 150 miles from my home.

            Ambient Temperature
            According to the National Weather Service (NWS), the temperature in my area at the start of the trip was 74 deg F (23 deg C). The temperature was expected to climb to the low 80s F (high 20s C) by the time I reached my destination so I'm taking the mean ambient temperature during the trip as ~ 80 deg F (27 deg C), for reference.

            Route, Driving Modes and Temperatures (150 mile course)
            1. Startup (baseline) temperature: 71 deg F (22 deg C).

            2. After 3-miles of intown and suburban running between origin and I-287: temp 84 deg F (29 deg C).

            3. Running 23 miles on I-287 to exit at I-87. Speed range 65-80 MPH; typical cruise 70-75 MPH. Temps: 83-85 deg F (28-29 deg C).

            4. Running 34 miles on I-87 to exit at I-84. Speed range 65-80 MPH; typical cruise 70-75 MPH. Temps: 88-89 deg F (31-32 deg C).

            5. Running 51 miles on I-84 to exit at US 7. Speed range 60 to 75 MPH; typical cruise 65-70 MPH. The downgrade on I-84 between I-87 and the Hudson River valley and bridge crossing has posted lower speed limits (with cops often lying in wait) so this is a decreased speed segment. Temps: 90-94 deg (32-34 deg C).

            6. Running 11 miles on US 7 (2-lane hgwy) to exit at US 202 in New Milford, CT. Construction, traffic lights, typical speeds of 35-45 MPH. Temps: 90-100 deg F (32-38 deg C), the upper range temps due to traffic light stops.

            7. Running 23 miles on US 202 (2-lane hgwy) to a point ~ 5 miles from destination. Occasional traffic lights, typical speeds of 40-50 MPH. Temps: 90-96 deg F (32-36 deg C).

            8. Last 5-miles: Intown driving, traffic and traffic lights. Max temp: 105 deg F (41 deg C) at shutdown.

            Results
            Maximum running temperature differential (excluding temps only seen in heavy traffic or traffic light stops) between baseline and highest temperature observed: 96 - 71 = 25 deg F (308.71 - 294.82 = 13.89 K). Percentage rise over baseline temp = 4.7%.

            However, if the running temperature differential is based on the estimated reference mean ambient air temperature of 80 deg F, then: 96 - 80 = 16 deg F (308.71 - 299.82 = 8.89 K). In this case, percentage rise over ambient = 3%.

            Conclusion and Discussion
            This was the first test mission where both the maximum running air box temperature (96 F; 36 C) and the estimated reference mean ambient air temperature (80 F; 27 C) were above the defined standard air temperature used for measuring SAE net HP (77 F; 25 C).

            Again, two conclusions are immediately apparent. The first is that an inspection of the data indicates a slowly rising running air box temperature as the trip progressed, probably accounted for by the steady increase in ambient air temperature during the duration of the ride. As established in earlier test missions, above a certain road speed only a change in the ambient air temperature, not trip length, affects air box temperature. The second is that the small percentage increase in maximum air box temperature over startup (4.7%), and the even smaller increase over the estimated reference mean ambient air temperature (3%) indicates that the modified OEM air intake system, as configured on this test vehicle, seems to be very efficient at providing relatively cool air (i.e. air close to the ambient in temperature) to the intake system.

            We can calculate the HP loss due to the difference between the observed maximum air box temperature and the SAE standard air temperature either by multiplying the rated HP by the square root of the change in absolute temperature (Kelvin or Rankine) or by using an online calculator. It can be shown that the 2.0L FS-DE engine rated at 130 HP will develop 127.76 HP (a loss of 2.24 HP, or 1.7%) at an intake air temperature of 96 deg F (36 deg C), all else being equal.

            So far, this summer has been a relatively cool one here with very few really hot days. I'm hoping for a hot spell with temperatures in the 90s, in conjunction with my ability timewise to run another test mission, in order to study the effect on air box temperatures. The results should be interesting.

            Just as a point of interest US 202 runs from Bangor, ME to, I think, Wilmington, DE bypassing all larger cities on the way, including NYC. An old-timer trucker once told me that before the Interstates, US 202 used to be one of the main truck routes from New England points to the mid-Atlantic states. Interestingly, US 202 also runs through my town.


            Happy Motoring!
            Last edited by goldstar; 05-01-2010, 07:11 AM.
            02 DX Millenium Red - The Penultimate Driving Machine
            MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
            MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
            Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
            MP3 Shifter, Knob and Aluminum Pedal Set
            Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
            Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
            Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
            Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
            Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
            Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
            Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
            Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

            Comment


              #7
              Calculating Intake Air Velocity

              Introduction
              As the two references cited above indicate, one by AEM and one by Pulkrabek, and in line with my own humble observations, intake air temperature depends both on the ambient and on the speed with which the intake air passes through the induction system. Given a fixed ambient temperature, the intake air will rise to its highest temperature at idle where engine rpm is lowest, and will fall to its lowest point above a certain speed as the rpm increases. I thought it would be interesting to quantify the mean air velocity through the intake duct to see how it relates to both engine rpm and intake air temperature.

              In order to accomplish this task, it's first necessary to calculate the mean piston speed (MPS) of the engine. This is an important parameter used to analyze many aspects of engine performance beyond the use we'll put it to here. In actual fact, piston speed varies from zero to a maximum and back to zero during the course of a single stoke, but it's the average or mean speed that concerns us now. The MPS is usually calculated in terms of feet/minute (fpm), but for our purposes feet/sec (fps) or (m/sec) will be more convenient. Since the piston makes two strokes in one crankshaft revolution, the formula is as follows:

              MPS, fpm = (2 x stroke, in inches) x (rpm/12)
              or, since 304.8 mm = 1'
              MPS, fpm = (2 x stroke, in mm) x (rpm/304.8)

              Since both numerator and denominator can be divided by 2, the formulas become:
              MPS, fpm = stroke, in inches x (rpm/6)
              MPS, fpm = stroke, in mm x (rpm/152.4)

              For our purposes, converting the formulas to yield fps values
              gives us the following two working formulas:
              MPS, fps = stroke, in inches x (rpm/360)
              MPS, fps = stroke, in mm x (rpm/9144)

              Reference: Auto Math Handbook, by John Lawlor; Chapter 3, Piston Speed, pages 17-21.

              Now we're in a position to calculate the mean air velocity through the intake duct. This involves multiplying the MPS, in fps or m/sec, at the rpm of interest, by the ratio of the diameter squared of the engine bore to the diameter squared of the intake duct. This gives us the following formulas:
              Mean Air Velocity, fps = MPS, fps x (D squared/d squared)
              Mean Air Velocity, m/sec = MPS, m/sec x (D squared/d squared)

              where, D = diameter of bore; d = diameter of intake duct

              Reference: The Design and Tuning of Competition Engines, Fifth Edition, by Philip H. Smith; Chapter 27, Definitions, Constants and Formulas, page 459.

              As is self evident, the diameter of the intake duct varies along its length. I've chosen to utilize the i.d. of the 90 deg elbow that connects the snorkel to the air box as the nominal diameter of the intake system for the purpose of example. The i.d. of the rubber hose, at the MAF end, connecting MAF sensor to TB has a similar dimension, although it tapers to a smaller dimension at the TB end. The air box of course has very large dimensions. In any case, consider the chosen measurement as representative, generally, of dimensions in the intake duct.
              Nominal intake duct i.d. = 64mm (2.5”)

              Measurement Choices
              The following details apply to the 2.0L FS-DE engine but of course can be configured for your own choice of engine.
              Bore: 83mm (3.268”)
              Stroke: 92mm (3.622”)
              D squared: 6889
              d squared: 4225

              I've selected three rpm points as representative of low velocity, high velocity, and very high velocity air flows. The first naturally is idle rpm, the lowest possible operating speed. With my digital tach, the fully-warmed up idle, no AC, fluctuates between 690 and 700 rpm. Therefore, 700 rpm is the low point. For the high point, I've selected the rpm associated with 65 MPH in 5th gear. Why? Because it's a common cruising speed and, from my own testing, one high enough to insure sufficient air flow to overcome low velocity intake air heating. Finally, I'll use the rpm associated with 80 MPH running because it's typically the highest consistent cruising speed I use in over the road driving (where feasible).

              Idle rpm: 700
              Rpm @ 65 MPH cruise, 5th gear: 2900
              Rpm @ 80 MPH cruise, 5th gear: 3580

              Calculations
              At 700 rpm, idle:
              MPS, fps = 92 x (700/9144) = 7.04 fps (2.15 m/sec)
              Mean Air Velocity, fps =7.04 x (6889/4096) = 11.84 fps (3.61 m/sec)

              At 2900 rpm, 65 MPH Cruise:
              MPS, fps = 92 x (2900/9144) = 29.18 fps (8.89 m/sec)
              Mean Air Velocity, fps = 29.18 x (6889/4096) = 49.08 fps (14.96 m/sec)

              At 3580 rpm, 80 MPH cruise:
              MPS, fps = 92 x (3580/9144) = 36.02 fps (10.98 m/sec)
              Mean Air Velocity, fps = 36.02 x (6889/4096) = 60.58 fps (18.47 m/sec)

              Conclusions
              Compared with idle speed air flow, mean air velocity at 65 MPH is 4.15 times more rapid and that at 80 MPH is 5.12 times faster. Clearly, a correlation exists between intake air velocity and heat absorbtion by the intake air.

              Just for the hell of it, the Mean Air Velocity at 6000 rpm (vehicle speed determined by gear ratio) = 101.53 fps (30.95 m/sec) which is 8.58 times faster than the air flow at idle.

              Since the intake used on the test vehicle is arranged to provide ram air due to its forward motion, an additional factor has to be considered in reference to the mean air velocity through the intake. Assuming perfect ram, at 65 MPH the theoretical air velocity through the intake duct is 95.33 fps (29.06 m/sec), and at 80 MPH it becomes 117.33 fps (35.76 m/sec). In both cases, the air velocity due to ram is considerably higher than that due to the downward movement of the pistons. Although determining the effect this has on intake air cooling is beyond my capabilities, it's undoubtedly a factor that enters into the process. For further information, go to:


              Happy Motoring!
              Last edited by goldstar; 05-02-2010, 05:18 PM.
              02 DX Millenium Red - The Penultimate Driving Machine
              MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
              MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
              Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
              MP3 Shifter, Knob and Aluminum Pedal Set
              Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
              Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
              Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
              Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
              Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
              Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
              Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
              Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

              Comment


                #8
                Test Mission No. 5 (August 2007)

                A trip to visit a friend located 61 miles from my home.

                Ambient Temperature
                This was what I had been waiting for as it doesn't get much hotter than this in my area and not that often. According to the NWS, the local temperature at the start of the journey was 95 deg F (35 deg C). Near the end of the run, a local bank's outside temperature display's reading was also 95 deg F so it's safe to assume that this figure can be taken as the mean ambient air temperature throughout the length of the trip, for reference.

                The run took place on August 3, which was a Friday and commenced at 3:45 pm. These factors are important to note as they both had an influence on the subsequent observed temperatures for the following reasons: During the summer months, many NJ residents spend their weekends along the state's coastal areas, traveling there during Friday's late afternoon and early evening time periods (and returning home Sunday night). The main route taken to reach these shore points is the Garden State Parkway (GSP) and to a lesser extent the NJ Turnpike (NJT), both roads which I had to utilize as the most direct way to get to my destination. Although 3:45 pm is normally too early to be associated with rush hour traffic, on Fridays, shore-bound people tend to leave work earlier than normal to beat the horrendous traffic jams seen in the late afternoon and evening hours ensuring that the 3:45 time period sees heavier than normal traffic. This results in some congestion and slow downs on what are normally high-speed roads and is reflected, to some degree (no pun intended), in the temperature readings.

                Route, Driving Modes and Temperature Readings (61 mile course)
                1. Startup (baseline) temperature: 111 deg F (44 deg C).

                2. After 4-miles of intown, suburban, and highway running between origin and I-280: temp 117 deg F (47 deg C).

                3. Running 16 miles on I-280 to exit at NJT
                a. First 11 miles: Speed range 60-80 MPH; typical cruise 70-75 MPH. Temps: 106-108 deg F (41-42 deg C). Traffic light to moderate.

                b. Next 2-miles: I-280 merges to two lanes causing congestion, very slow speeds and 1st and 2nd gear running only. Temp at end of section: 146 deg F (63 deg C).

                c. Final 3-miles: back to 3-lanes, congestion ends: Speed range 65-80 MPH. Temp at end of section: 114 deg F (46 deg C). Traffic moderate.

                4. Running 18 miles on NJT to exit at GSP. Speed range 65-80 MPH; typical cruise 70-80 MPH. Temps: 109-110 deg F (43 deg C). Traffic light to moderate.

                5. Running 20 miles on GSP to destination exit. Speed range 60-75 MPH; no typical cruise. Temps: 109-116 deg F (43-47 deg C). Traffic moderate to heavy, several slow-downs from high-speed running.

                6. Last 3-miles: Suburban driving, no traffic lights. Temp: 123 deg F (51 deg C) at shutdown.

                Results
                Note that although the ambient temperature was 95 deg F (35 deg C), and the engine had not yet been operated that day, the startup temp was 111 deg F (44 deg C). This is due to the heating effects of the sun which causes the underhood temperature to be hotter than the ambient during the warmer months of the year and has been noted before but not to this extent. This effect is maximized since the driveway is located on the south side of the house and thus the test vehicle is exposed to the direct radiation from the sun. Therefore, the startup temp will be excluded as a reference point in favor of the ambient.

                Maximum running temperature differential between ambient and lowest temperature observed: 106 - 95 = 11 deg F (314.26 - 308.15 = 6.11 K). Percentage rise over ambient = 2%.

                Maximum running temperature differential between ambient and highest temperature observed (excluding temps only seen in intown, suburban or slow-speed, heavy traffic driving: 116 - 95 = 21 deg F (319.82 - 308.15 = 11.67 K). Percentage rise over ambient = 3.8%.

                Maximum temperature differential between ambient and highest temperature observed: 146 - 95 = 51 deg F (336.48 - 308.15 = 28.33 K). Percentage rise over ambient = 9.2%.

                Conclusion and Discussion
                Two conclusions immediately stand out. The first is that given a constant ambient temperature, fluctuations in air box temperature are primarily a function of the various speed profiles generated by prevailing traffic conditions. Thus, where mean speed in MPH could be kept high, air box temperatures remained relatively low and where frequent slow-downs from high-speed running were necessary or where very low-speed running was the rule, air box temperatures climbed.

                The second is that where constant running at speed above a certain minimum is possible, the modified OEM air intake system on the test vehicle did a credible job of providing relatively cool air to the intake system, even when the ambient temperature was high. This is illustrated by the only 2% temp difference between ambient and the lowest recorded running temp of 106 F, and the not much larger difference of 3.8% at the highest recorded running temp of 116 F. Of course, the temp difference of 9.2% between ambient and the maximum recorded temp of 146 F is much larger but can be considered an aberration since the temp quickly falls once more normal running is restored.

                Since all the observed temperatures were above the SAE standard temperature of 77 F (25 C) used to calculate SAE net BHP, it would be interesting to calculate the effect of elevated intake air temperatures on HP output. Given that the 2.0 L FS-DE engine is rated at 130 HP, using the usual method of calculation will indicate the reduced HP available.

                At the ambient of 95 F (35 C): 127.84 HP

                At the minimum running air box temp of 106 F (41 C): 126.62 HP

                At the maximum running air box temp of 116 F (47 C): 125.52 HP

                At the maximum air box temperature of 146 F (63 C): 122.37 HP

                It appears that you drag racers waiting on the line or street racers waiting at the stop light might gain some advantage from figuring out how to cool down the intake duct before taking off.


                Happy Motoring!



                02 DX Millenium Red - The Penultimate Driving Machine
                MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
                MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
                Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
                MP3 Shifter, Knob and Aluminum Pedal Set
                Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
                Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
                Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
                Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
                Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
                Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
                Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
                Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

                Comment


                  #9
                  Test Mission No. 6 (December 2007)

                  I decided to post this test mission when I realized that the five previous ones involved, to a greater or lesser degree, interstate highway running with its attendant high speeds. Since we've already seen that vehicle speed, below a certain minimum also affects air intake temperature (because of the length of time a given mole of air takes to traverse the intake duct), I thought it would be interesting to post the data from a trip that involved only suburban running with the lower driving speeds typical of that environment.

                  On the day of the run, December 6th, the temperature was unusually and unseasonably cold for this time of year since it wasn’t even technically winter yet.

                  Route, Driving Modes and Temperatures (~ 20 mile course)
                  Startup (baseline) temperature: 22 deg F (-6 deg C).

                  The trip involved a short amount of intown running followed by a stretch of 4-lane US highway with the bulk and remainder of the run on 2-lane backroads. Traffic was moderate to light and the maximum speed attained was 56 MPH for a very brief period of time. The overall typical cruising speed was ~ 40MPH, and with only a few brief traffic lights and stop signs, the car was in motion for virtually the entire journey.

                  The typical running temperature centered closely around 31 deg F, (-.56 deg C).

                  The highest temperature recorded was 37 deg F (2.8 deg C). This occurred at a traffic light stop, but once underway the temperature returned to the typical running temperature.

                  Results
                  Maximum running temperature differential between ambient and highest typical running temperature observed: 31 - 22 = 9 deg F (272.59 - 267.59 = 5 K). Percentage rise over ambient = 1.9%.

                  Maximum temperature differential between ambient and highest temperature observed: 37 - 22 = 15 deg F (275.93 - 267.59 = 8.34 K). Percentage rise over ambient = 3.1%.

                  Conclusion and Discussion
                  The most obvious conclusion is that even at the lower running speeds typical of suburban driving, compared with the much higher ones possible on the interstates and in rural areas, the running air intake temperature showed only a slight rise over the ambient. This finding, of course, is moderated by the fact that due to the light traffic and favorable traffic light patterns, the test vehicle was in motion for most of the trip. We've already seen that depending on the length of vehicle dwell time, the air intake temperature can rise quickly and to unexpectedly high levels both during idling and slow-speed running.

                  One can also question whether the small temperature rise was also a function of the rather low (below freezing) starting temperature. From past experience, it’s likely that if the ambient were in the 80s or 90s, the temperature rise could have been greater under similar driving conditions. I hope to replicate these conditions and run a second trial next Spring or Summer - stay tuned for the results.

                  Miscellaneous
                  Because of the lowered air intake temperature, there is a proportionate increase in BHP output. After getting use to the performance envelope of my car in the warm weather, the noticeable increase in performance at these low temperatures feels pretty good, and at least partially offsets the other problems that cold weather brings.

                  Two things I've mentioned previously about my air intake mod: one, on acceleration air intake sound could be heard (it wasn’t obtrusive to me) although not nearly as loud as that produced by an aftermarket SRI or CAI; two, as the ambient air temperature decreased the air intake sound increased. This was the opinion not only of me but also of others who rode with me in the car. I attributed this to the greater density (weight) of the colder intake air. However, since installation of my Racing Beat exhaust system which dominates all other sounds on acceleration, I can no longer hear the air intake noise. Well, you win some and you lose some, I guess.


                  Happy Motoring!
                  02 DX Millenium Red - The Penultimate Driving Machine
                  MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
                  MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
                  Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
                  MP3 Shifter, Knob and Aluminum Pedal Set
                  Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
                  Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
                  Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
                  Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
                  Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
                  Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
                  Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
                  Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

                  Comment


                    #10
                    Test Mission No. 7 (August 2008)

                    As this occurred during the first day of our vacation, I hadn't intended to record temperature data. However, because of the nature of the run, and its length, a 245-mile trip from our home to Lowell MA, I thought the obtained data might be of interest to some of our members. All but the first 3-miles and last 2-miles took place on Interstate highways and one expressway, and with the exception of two pit stops, involved continuous, almost constant-speed cruising for virtually the entire length of the trip. This was possible due to the light traffic throughout (typical of a weekday) from our point of origin to our destination.

                    Route, Driving Modes and Temperature Readings (245 mile course)
                    We drove from NJ through NY and then CT to MA using direct connections from I-287 to I-684 to I-84 to I-90 (the Mass Pike) to I-290 to I-495 to the Lowell Connector expressway.

                    Startup (baseline) temperature: 75 deg F (24 deg C). This has been typical of our early summer mornings here as we've had a generally cool, wet summer, so far. After noting this temperature, and the fact that the running temperature seemed to stabilize at 86 deg F (30 deg C) after ~ 5-miles of Interstate cruising, I put all thoughts of recording further temperature changes out of my mind. However, occasional glances at the gauge indicating extremely stable readings caused me to reconsider.

                    The speed limits for the most part were 65 mph for all the Interstates over the entire route with some restrictions in a few limited areas (for example, over the Tappan Zee bridge which crosses the Hudson River in NY state, in some urban areas such as around Hartford, CT, and on the Lowell Connector).

                    Consequently, due to the light traffic conditions as already noted, I was able to maintain a cruising speed of 70 to 75 mph, with occasional bursts to 80 to move around trucks and slower-moving traffic, for virtually the entire length of the trip. During this time, the air box temperature never varied outside the limits of 84 to 86 deg F (29 to 30 deg C).

                    The only major temperature variations occurred during our aforementioned two pit stops. We stopped first on I-84 just after the road crosses the NY/CT border at a CT Welcome Center for the usual reason and to obtain the latest official CT road map. The car was parked for ~ 10 minutes, and on startup the gauge read 105 deg F (41 deg C) obviously due to heat soak, but after a short period of running at Interstate speeds, the temperature again stabilized at 84 to 86 deg F.

                    The second pit stop of ~ 10 miutes at a MA Welcome Center on I-495 where we also obtained a map, resulted in a heat soak induced startup temperature of 107 deg F (42 deg C) which again returned to the 84 to 86 deg F range once back on the road.

                    These heat soak temperatures were relatively low due to the short engine off times. If we'd been parked for any appreciable length of time, the air box temperatures would have been much higher and taken longer to return to their stable point.

                    Results
                    Maximum temperature differential between baseline and constant running mode: 86 - 75 = 11 deg F; 30 -24 = 6 deg C (303.15 K - 297.04 K = 6.11 K). Percentage rise over baseline temperature = 6.11/297.04 = 2%.

                    Conclusion
                    As can be seen, a remarkably stable, consistent, and limited range of temperature readings over a long period of time. This is undoubtedly due to the virtually constant cruising speed and continuous running of the test vehicle for the bulk of the trip. Again, the relatively small spread between the ambient and the air box temperatures also attests to the effectiveness of the modification exposing the air inlet to ambient temperature air. I also think it's fair to conclude that the Cyberdyne temperature gauge and sending unit are highly stable, accurate units giving consistent readings over long time periods yet rapidly responding to parameter change as in the case of the heat soak indications. This rapid response to changing temperature conditions has been a well-observed characteristic of the gauge in all the temperature studies reported in this thread.

                    Some may also note that the indicated running temperatures are rather low for the summer season in this part of the country. Obviously, if the ambient had been higher, so would have been the measured temperatures - we know this from the results of previous test missions. However, the measurement day was a rather cool one which seemingly is the norm this summer for the New England area as many of the local residents we met on our trip claim that the climate is wetter and cooler than is typically the case for this time of year. On every day of our vacation, except the first and last one, we experienced rain and temperatures on the cool side.

                    Happy Motoring!
                    02 DX Millenium Red - The Penultimate Driving Machine
                    MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
                    MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
                    Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
                    MP3 Shifter, Knob and Aluminum Pedal Set
                    Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
                    Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
                    Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
                    Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
                    Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
                    Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
                    Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
                    Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

                    Comment


                      #11
                      Test Mission No. 8 (January 2009)

                      This is a repeat of Test Mission No. 3. I decided to record the data and present it because it represents the coldest temperatures I've yet encountered on a long-distance trip. As a consequence, I thought some of you would find it of interest. Again, for job related reasons, I traveled to the same engineering company as before, located in NY state.

                      A fast-moving Alberta Clipper was bringing light snow to the area I'd be traveling through, and because of the extremely cold temperatures the snow could likely become icy and slippery when reaching the ground, potentially slowing me down. That, as well as the fact that I planned to stop for breakfast at a diner along the way, prompted me to start my trip at 6 am. It was still dark out at that hour. Before leaving, I checked the NWS temperature for my town (16 deg F; -9 deg C), and for that of my destination (9 deg F; -13 deg C). My direction of travel was almost due north.

                      Route, Driving Modes and Temperatures (73 mile course)
                      The route was as follows: From my home to the entrance to I-287, 3-miles of intown and suburban driving; I-287 to entrance to I-87 (the NY State Thruway), 22 miles; I-87 to point of exit, 34 miles; rural, 2-lane state highway from I-87 to destination, 14 miles.

                      Startup (baseline) temperature: 18 deg F (-8 deg C).

                      Running temperatures: Driving north along the Interstates, the air box temperature progressively fell to a low of 11 deg F (-12 deg C) with a range of 11 to 13 deg F (-12 to -11 deg C) as indicated by the gauge, until I reached my exit. Because of the snow (which was still falling lightly) I never exceeded the posted speed limit of 65 mph, much of the time doing less. Once on the state highway, the temperature remained at 11 deg F (-12 deg C) maximum until I stopped for breakfast. This effectively terminated the record-keeping part of the journey as I'll explain shortly.

                      My usual breakfast, 6-days a week, is a bowl of nutritious whole-grain oatmeal. On either Saturday or Sunday, we'll have a family breakfast which for me typically consists of an egg-beater omelet filled with Alpine Lace low-fat swiss, mushrooms, and sometimes, tomato or asparagus added. Garnish that with 2 MorningStar Farms vegetable-based sausage links and Thomas' Light Multi-Grain English muffins (with all the nookies and crannies you've come to expect from Thomas), and a cup of Folger's Classic Roast, and not only is that meal delicious, but also healthy and virtuous.

                      The great thing about following the WeightWatcher's diet is that when you're out you can occasionally diverge from it without compromising your health or having to feel sinfull. At the diner, I had a 3-egg omlet with cheddar cheese, home fries and whole wheat toast. Coffee too, of course. Yum! Just like when we go on vacation.

                      But I digress.

                      After leaving the diner and starting the engine, the temperature gauge read 60 deg F due to heat soak (as I knew it would) so, although the temperature decreased as I neared my destination (only a short distance away), this data is not included here. After a long-enough run, the temperature would have returned to its previous lower value.

                      Results
                      Maximum running temperature differential between baseline and lowest temperature observed: 18-11 = 7 deg F (265.37-261.48 = 3.89K). That's only a 1.5% decrease, nothing to write home about but not surprising given that this was virtually a constant speed run with no appreciable traffic to slow things down and heat things up.

                      Conclusion and Discussion
                      We've already determined that once the engine and bay have reached operating temperature, as long as the ambient temperature remains constant, the length of the run seems not to affect temperature change. Therefore it's likely that the progressive decrease in air box temperature over time seems to have been a function of the progressive decrease in ambient temperature as I continually headed north.

                      The most striking thing about the drive was how powerful the car felt once fully warmed up. As I already stated, these are the lowest sustained temperatures I believe I've yet experienced on a drive of this length. This is not surprising given that the FS-DE engine outputs 139 BHP at 11 deg F. This is a 6.8% increase over stock, although with my engine the increase is probably even more.

                      Driving wasn't too bad; cornering was okay but braking sometimes got a little tricky with an occasional slide, but my fault for coming in a little hot on occasion. At these temperatures, ice forms very rapidly. All-in-all a good run and I really enjoyed breakfast.


                      Happy Motoring!
                      02 DX Millenium Red - The Penultimate Driving Machine
                      MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
                      MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
                      Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
                      MP3 Shifter, Knob and Aluminum Pedal Set
                      Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
                      Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
                      Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
                      Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
                      Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
                      Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
                      Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
                      Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

                      Comment


                        #12
                        Miscellaneous Ramblings

                        Both Formula 1 and IndyCar are spec racing series where every parameter of engine and chassis design is regulated by the sanctioning body with the intent of ensuring little or no performance variation among the competing race cars. Currently taken to extremes in IndyCar with only one engine builder (Honda), and one chassis builder (Dallara), even the variety of engine and chassis builders in Formula 1 produce engines with little variation in power output. In line with this philosophy it's instructive to note the following FIA Technical Regulations posted in the Engines and Kinetic Recovery Systems (KERS) Section, available at:
                        Don't miss a Formula 1 moment – with the latest news, videos, standings and results. Go behind the scenes and get analysis straight from the paddock.


                        5.12 Engine Intake Air:
                        5.12.1 Other than injection of fuel for the normal purpose of combustion in the engine, any device, system, proceedure, construction or design the purpose or effect of which is any decrease in the temperature of the engine intake air is forbidden.
                        5.12.2 Other than engine sump breather gases and fuel for the normal purpose of combustion in the engine, the spraying of any substance into the engine intake air is forbidden.

                        A Lost Opportunity
                        On August 10th, 2009, my wife and I took a vacation trip to Newport, RI a distance of about 200 miles from our home. We recorded air box temperature data on that first day intending to post it when we returned home. Unfortunately, somehow I lost the data. Bad goldstar.

                        Finally, the Big 0
                        The winter of 2008-09 had been an exceptionally cold one in my area and on the morning of January 17th, 2009, knowing that extremely low temperatures had been predicted during the previous night, I checked the NWS temperature for my town. Lo and behold, 0 deg F (-18 deg C). I just had to see what the air box temperature was so outside I went to start the Protege. Air box temperature at startup: 4 deg F (-16 deg C; 255.37 K). Darn it all, I was really hoping to see 0 deg F for the first time but at least this is the lowest reading I've ever seen on the gauge so I had to record it for posterity.

                        Happy Motoring!

                        The ghost lines seen outlining the gauge numerals in the photo below are an artifact of the camera; they don't appear to the naked eye.
                        Attached Files
                        Last edited by goldstar; 05-03-2010, 09:20 AM.
                        02 DX Millenium Red - The Penultimate Driving Machine
                        MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
                        MSP Springs, Struts, Stabilizer Bars, Trailing Links, #3 Engine Mount
                        Kartboy Stabilizer Bar Bushings; Nyloil Shifter Bushings; Red Line MT-90 Gear Oil
                        MP3 Shifter, Knob and Aluminum Pedal Set
                        Suvlights HD Wiring Harness; Osram Night Breaker H4 Bulbs; Exide Edge AGM Battery
                        Summer: 5Zigen FN01R-C 16 x 7" Wheels; Yoko S.drive 205/45-16s
                        Winter: Enkei OR52 16 x 7" Wheels; Falken Ziex ZE-912 205/45-16s
                        Modified OEM Air Intake; Racing Beat Exhaust System; Techna-Fit SS Clutch Line
                        Denso SKJ16CR-L11 Extended Tip Spark Plugs; Magnecor Wires
                        Power Slot Front Brake Rotors; Techna-Fit SS Brake Lines; Hawk HPS Pads
                        Red Line Synthetic Engine Oil; C/S Aluminum Oil Cap
                        Cyberdyne Digital Gauges: Tach; Ambient Air Temp; Voltmeter

                        Comment


                          #13
                          Noticeable increase for me by just cuttin out the spot for more cold air. worthwhile mod!

                          Comment

                          Working...
                          X