Hey allcan someone explain to me what tire sizes mean? I currently run 205/50 15s, and my tires are 205/55 15s. I know oem on the 99 ES are 195/55 15s. What does this mean and will I notice a difference. Thanks NIk
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Originally posted by Zmanpro63Hey allcan someone explain to me what tire sizes mean? I currently run 205/50 15s, and my tires are 205/55 15s. I know oem on the 99 ES are 195/55 15s. What does this mean and will I notice a difference. Thanks NIk
205/50-15
The first number, 205, is the nominal tread width in mm.
The second number, 50, is the aspect ratio of the tire in %. It specifies the height of the sidewall as a percentage of the tread width. In this case, sidewall height is 50% of tread width or ~ 4". To calculate: 50% of 205 mm = 102.5 mm which = 4.0354331 inches.
The third number is the wheel diameter.
Aspect ratio affects two characteristics: handling and ride comfort. In general, an increase in sidewall height reduces handling to some degree because of increased tire squirm during cornering. At the same time, there is some increase in ride comfort. A decrease in sidewall height likewise improves handling ability and decreases ride comfort.
It's interesting to note that the 205/50 tire has a smaller sidewall height than does the 195/55 tire even though the 205 has the wider tread.02 DX Millenium Red - The Penultimate Driving Machine
MP3 Strut Tower Bar kit; Cusco Front Lower Arm Tie Bar
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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
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I plan on getting the 205/55s since I cant get the tire I want in a 205/50 but they do offer a 225/50, would this be the best bet for performance? The tire is the Falken Ziex 512, they do offer a 205/50 in an H rating but I want the V rating and that comes in 195/55, 205/55 and 225/50, any ideas?
Originally posted by goldstarFor example:
205/50-15
The first number, 205, is the nominal tread width in mm.
The second number, 50, is the aspect ratio of the tire in %. It specifies the height of the sidewall as a percentage of the tread width. In this case, sidewall height is 50% of tread width or ~ 4". To calculate: 50% of 205 mm = 102.5 mm which = 4.0354331 inches.
The third number is the wheel diameter.
Aspect ratio affects two characteristics: handling and ride comfort. In general, an increase in sidewall height reduces handling to some degree because of increased tire squirm during cornering. At the same time, there is some increase in ride comfort. A decrease in sidewall height likewise improves handling ability and decreases ride comfort.
It's interesting to note that the 205/50 tire has a smaller sidewall height than does the 195/55 tire even though the 205 has the wider tread.
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Originally posted by Zmanpro63I plan on getting the 205/55s since I cant get the tire I want in a 205/50 but they do offer a 225/50, would this be the best bet for performance? The tire is the Falken Ziex 512, they do offer a 205/50 in an H rating but I want the V rating and that comes in 195/55, 205/55 and 225/50, any ideas?
A 205/55 tire gives you a taller sidewall than stock (bad for handling) and increases your speedo error. It will also reduce acceleration because it effectively raises (lowers numerically) your final drive ratio. The increased weight of the tire/wheel combo will also cause a performance penalty.
A 225/50 tire has all the disadvantages of the 205/55 and then some. Additionally, a 225 tire is not an optimum choice for 6" wide rim as the tire could roll on the rim under hard cornering-7" width would be better for this size.
02 DX Millenium Red02 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
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Originally posted by goldstarYou state OEM for your car is 195/55-15 and I'm assuming you have a 6" wide rim. IMO, your best choice for all around performance is a 205/50 tire. This width and aspect ratio is generally considered an acceptable mounting on a 6" wide rim and it will not cause too much error in your speedo reading as a check with miata tirecalc will demonstrate. You get the advantage of a wider tire and lower sidewall-both good for handling.
A 205/55 tire gives you a taller sidewall than stock (bad for handling) and increases your speedo error. It will also reduce acceleration because it effectively raises (lowers numerically) your final drive ratio. The increased weight of the tire/wheel combo will also cause a performance penalty.
A 225/50 tire has all the disadvantages of the 205/55 and then some. Additionally, a 225 tire is not an optimum choice for 6" wide rim as the tire could roll on the rim under hard cornering-7" width would be better for this size.
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Originally posted by Zmanpro63So I should get the 205/50 with the H rating? I just always thought that a higher speed rating equaled better performance. I doubt I will reach 130mph which is what the H rating cooresponds to, and I certainly wont be cruising at that speed but I figured a 149mph rating would be better. Maybe Im just paying too much attention to the numbers? Any suggestions will be greatly appreciated then I can put this mother too bed. Thanks Nik
02 DX Millenium Red02 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
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Originally posted by goldstarI can't really help you with the problem of speed rating. Both Discount Tire and 1010 Tire advise against downgrading the speed rating from the OEM recommendation. They claim that doing so will adversely affect handling but by how much is unknown. I know that for any given tire available in different speed ratings, the higher rated one is generally said to be of stronger construction and to have somewhat better handling characteristics. I don't know how much of a performance decrement would occur going from a V to an H-rated tire since I've never done that myself but perhaps someone else here who has made the switch could better advise you. For most driving situations, the difference might be negligible.
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