Alright, I give up, what do the numbers for tires mean!!??
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From: Mesa, AZ
Car: A Camaro
Engine: Weak
Transmission: Weaker
Alright, I give up, what do the numbers for tires mean!!??
Ok, lets say we have a 315/35/17 Tire. I understand it's for a 17" rim, but 315? centimeters? is that the outer diameter? tread width? Please help me, I think this is kind of esential information if I want to think I know anything about cars. Thank you for helping the mentally challenged with a 3.85 GPA.
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From: Loveland, OH, US
Car: 4
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Transmission: 5
315 = section width (the widest part of the tire, more or less) is 315 mm wide.
35 = aspect ratio; means the sidewall height is 35% of the section width.
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"So many Mustangs, so little time..."
ICON Motorsports
35 = aspect ratio; means the sidewall height is 35% of the section width.
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"So many Mustangs, so little time..."
ICON Motorsports
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Joined: Jun 2000
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From: United States of America
Car: 1987 Chevrolet Camaro Z28 IROC-Z
Engine: L98
Transmission: TeamTripp Performance
Check out this link- http://members.aol.com/mmmm999/3rd-d...ires/tires.htm
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From: NE
Car: 82 camaro SC
Engine: 350
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Keep in mind that section width isn't tread width. Some tire companies 'cheat' the tires. Some 245/50's are wider than others.
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82 camaro--original steering wheel, brake/gas pedals, seats--everything else modified
82camaro
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82 camaro--original steering wheel, brake/gas pedals, seats--everything else modified
82camaro
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Width of street tires with DOT sizes are measured at the sidewall bulge not the actual tread patch left on the ground.
Also compare tire height.
315/35/17 is only 25.68" tall.
315mm X 35mm / 2450 = 4.34055" sidewall.
4.34055 + 4.34055 + 17" rim = 25.68" tall tire.
Lets look at the 245/50 with a 16 inch rim
245 X 50 / 2540 = 4.8228" sidewall. It has a taller sidewall than the other tire.
4.8228 + 4.8228 + 16 = 25.64" tall tire.
If you can squeeze that 17" rim tire under the fenders it would be a good swap. Even though it's wider with a smaller sidewall width, the tire is the same height as the 245/50. This means the speed calibration would be close enough that you wouldn't notice it.
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Follow my racing progress on Stephen's racing page
and check out the race car
87 IROC-Z Pro ET Bracket Race Car
383 stroker (carbed) with double hump cast iron heads and pump gas
461 Big Block installed and ready for the 2001 racing season
Best results before the 383 blew up
Best ET on a time slip: 11.857 altitude corrected to 11.163
Best MPH on a time slip: 117.87 altitude corrected to 126.10
Altitude corrected rear wheel HP based on power to weight ratio: 476.5
Best 60 foot: 1.662
Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association
87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley
Also compare tire height.
315/35/17 is only 25.68" tall.
315mm X 35mm / 2450 = 4.34055" sidewall.
4.34055 + 4.34055 + 17" rim = 25.68" tall tire.
Lets look at the 245/50 with a 16 inch rim
245 X 50 / 2540 = 4.8228" sidewall. It has a taller sidewall than the other tire.
4.8228 + 4.8228 + 16 = 25.64" tall tire.
If you can squeeze that 17" rim tire under the fenders it would be a good swap. Even though it's wider with a smaller sidewall width, the tire is the same height as the 245/50. This means the speed calibration would be close enough that you wouldn't notice it.
------------------
Follow my racing progress on Stephen's racing page
and check out the race car
87 IROC-Z Pro ET Bracket Race Car
383 stroker (carbed) with double hump cast iron heads and pump gas
461 Big Block installed and ready for the 2001 racing season
Best results before the 383 blew up
Best ET on a time slip: 11.857 altitude corrected to 11.163
Best MPH on a time slip: 117.87 altitude corrected to 126.10
Altitude corrected rear wheel HP based on power to weight ratio: 476.5
Best 60 foot: 1.662
Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association
87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley
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