Will bigger wheels/tires offset speedometer?
Thread Starter
Pro
Joined: Jan 2005
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From: Myakka City Florida
Will bigger wheels/tires offset speedometer?
I am considering getting the Corvette Garage Z07 wheels. The wheel sizes are 18x9 for the front and 18x11 for the rear. The tire size I am considering is 265/35/18 for the front, 295/35/18 for the rear (probably the Michelin run-flats). Will the bigger wheels/tires offset my speedometer? Will the 18's all around affect anything?
Safety Car
Joined: Jun 2003
Posts: 4,332
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From: Dayton, Ohio
Senior Member
CI 5-6-7-8 Veteran
The tires that you are looking at would be slightly different in size but not enough to throw your speedometer off enough to matter.
The overall diameter of the Michelin 265/35/18 is actually .3" smaller than the Goodyear (stock) 245/45/17.
The overall diameter of the Michelin 295/35/18 is actually .5" smaller than the Goodyear 275/40/18.
This would obviously cause a minimal change in the accuracy of the speedo but I dont think it would be enough to make much of a difference. If it really bothered you, you could have someone go in and reprogram the new tire sizes into the computer to recalibrate the speedo.
Also, in regards to your second question about running 18's all the way around, you should be fine. As long as your front and rear tires have a decent difference in their overall diameter you should be fine. The Michelin sizes you mentioned should be fine.
Good luck
The overall diameter of the Michelin 265/35/18 is actually .3" smaller than the Goodyear (stock) 245/45/17.
The overall diameter of the Michelin 295/35/18 is actually .5" smaller than the Goodyear 275/40/18.
This would obviously cause a minimal change in the accuracy of the speedo but I dont think it would be enough to make much of a difference. If it really bothered you, you could have someone go in and reprogram the new tire sizes into the computer to recalibrate the speedo.
Also, in regards to your second question about running 18's all the way around, you should be fine. As long as your front and rear tires have a decent difference in their overall diameter you should be fine. The Michelin sizes you mentioned should be fine.
Good luck
Le Mans Master
Joined: Aug 2002
Posts: 8,222
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From: Norfolk VA
I've got the same size tires on my car now. I did the math on it a while back and at 180mph on the speedometer, the car would actually be going 177 or 178
at sane speed, it's within 1mph, so it's not really an issue. Speedometers are only accurate to within a few mph, so you shouldn't even notice it.
at sane speed, it's within 1mph, so it's not really an issue. Speedometers are only accurate to within a few mph, so you shouldn't even notice it.
Team Owner
Joined: Sep 2002
Posts: 30,591
Likes: 4,617
From: Bonita Springs, Florida
Originally Posted by 2k1 Vette
The tires that you are looking at would be slightly different in size but not enough to throw your speedometer off enough to matter.
The overall diameter of the Michelin 265/35/18 is actually .3" smaller than the Goodyear (stock) 245/45/17.
The overall diameter of the Michelin 295/35/18 is actually .5" smaller than the Goodyear 275/40/18.
This would obviously cause a minimal change in the accuracy of the speedo but I dont think it would be enough to make much of a difference. If it really bothered you, you could have someone go in and reprogram the new tire sizes into the computer to recalibrate the speedo.
Also, in regards to your second question about running 18's all the way around, you should be fine. As long as your front and rear tires have a decent difference in their overall diameter you should be fine. The Michelin sizes you mentioned should be fine.
Good luck
The overall diameter of the Michelin 265/35/18 is actually .3" smaller than the Goodyear (stock) 245/45/17.
The overall diameter of the Michelin 295/35/18 is actually .5" smaller than the Goodyear 275/40/18.
This would obviously cause a minimal change in the accuracy of the speedo but I dont think it would be enough to make much of a difference. If it really bothered you, you could have someone go in and reprogram the new tire sizes into the computer to recalibrate the speedo.
Also, in regards to your second question about running 18's all the way around, you should be fine. As long as your front and rear tires have a decent difference in their overall diameter you should be fine. The Michelin sizes you mentioned should be fine.
Good luck
Safety Car
Joined: May 2003
Posts: 3,814
Likes: 105
From: Dearborn Heights Michigan
http://www.race-cars.net/calculators...alculator.html
Go to this web site and you can calculate MPH based on tire size, etc.
Fred
Go to this web site and you can calculate MPH based on tire size, etc.
Fred
