Announcement

Collapse
No announcement yet.

speedomiter accuracy?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    speedomiter accuracy?

    i just have one quick question.
    I just got 17" rims a toyo proxy wheels. they are a bout a inch or 2 taller than the stock wheels. By having this change in height throw my speedomiter off? i know to some cars it does but i dont know about our Proteges. and if the speedomiter is off the tach would still be correct since it is just mesuring the revolutions, right?

    -thanks for the help
    97 1.5L protege LX

    20% tint,
    17" rims (off for the winter)
    performance muffler
    2 10"subs
    other little things

    #2


    thur ya go
    According to my Anger Management Counselor, after 26 weeks of anger management class, I should be an expert when it comes to Anger Management...tell that to the guy who threw a starburst at my car in rush hour traffic...haha


    Todays thought of the day:

    Rice is great if your really hungry and want to eat 2000 of something.

    Mitch Hedberg

    Comment


      #3
      Originally posted by ricerocket97
      and if the speedomiter is off the tach would still be correct since it is just mesuring the revolutions, right?
      Incorrect, if it were based on engine speed (RPM) then the change in the wheel+tire diameter is going to change the calculation ratio between RPM and speed.

      If you think about it this way it helps. Assume that for every revolution the engine makes you get one rotation out of the tire (not the case, but easy on the math). Each of those rotations means that the vehicle travels a fixed linear distance. So, if you change the diameter of the wheels you still get one revolution of the wheel for each RPM, but you travel a different linear distance per tire rotation. Linear distance traveled versus time = speed.
      --JJB--
      '02 Silver Protegé5 - 5sp - no performance mods, no plans for them
      Kenwood Z919 -- Polk Audio speakers
      16" alloys w/ 205/50 Bridgestone RE750 (summer)
      15" steels w/ 195/55 Bridgestone Blizzak LM22 (winter)

      Moon roof - wind deflector - variable intermittent wipers - electrochromic mirror w/ temp & compass
      Winter/beater car: 1997 Mercury Mountaineer with 182k on it

      Comment


        #4
        just keep the damn circumfrence the same, bigger wheel smaller sidwall
        According to my Anger Management Counselor, after 26 weeks of anger management class, I should be an expert when it comes to Anger Management...tell that to the guy who threw a starburst at my car in rush hour traffic...haha


        Todays thought of the day:

        Rice is great if your really hungry and want to eat 2000 of something.

        Mitch Hedberg

        Comment

        Working...
        X