Tires
Thread Starter
Le Mans Master
Joined: Oct 2008
Posts: 8,884
Likes: 981
From: Whitby Ont.
Tires
I have a chance at 2-275/35 18s, my car takes 275/40-18s. Will this be much of a difference ? I understand that there is 1"difference in height, it will mess my speedometer up I m thinking,and increase rpms at the same speed as now.Not sure if it is a good idea to take these or not, they are brand new, and the price is right.
Opinions please.
Thanks Al
Opinions please.
Thanks Al
Melting Slicks
Joined: Mar 2006
Posts: 2,749
Likes: 377
From: South Florida FL
maybe if was a drag radial or a seasonal tire or something.
According to your avatar, that wheel/tire/height combination will visually bother me.
Performance wise, you're not going wider to compensate for the height difference, whilst loosing ride comfort. I'll put in some overtime personally rather than try save a penny.
According to your avatar, that wheel/tire/height combination will visually bother me.
Performance wise, you're not going wider to compensate for the height difference, whilst loosing ride comfort. I'll put in some overtime personally rather than try save a penny.
Drifting
Joined: Jun 2006
Posts: 1,302
Likes: 4
From: Palo Alto CA
Race Director
Joined: Aug 2003
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From: "It's 106 miles to Chicago, we've got a full tank of gas, half a pack of cigarettes, it's dark, and
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16-'17-‘18-'19
NCM Sinkhole Donor
The biggest thing that you need to worry about when running a shorter overall diameter tire in the rear is the implications on the traction control system. The system functions by monitoring the wheel speed of each wheel.
The system is expecting to see the front wheel turning faster than the rears - if you go with a a shorter tire in the rear, the T/C system will interpret that as wheel spin - and will invoke T/C. It is important to maintain at least an approximate 1/2" of differential of overall height front to rear - with the rear being taller and resulting in less revolutions per mile.
The system is expecting to see the front wheel turning faster than the rears - if you go with a a shorter tire in the rear, the T/C system will interpret that as wheel spin - and will invoke T/C. It is important to maintain at least an approximate 1/2" of differential of overall height front to rear - with the rear being taller and resulting in less revolutions per mile.
Heel & Toe
Joined: Jul 2011
Posts: 20
Likes: 0
From: Arlington Texas
I have a 2000 Corvette running non runflat Bridgestone. Would like to change to Michelin runflats but can only get the rears. Would I have any handling problems having runflats on the rear and non runflats on the front?
Tech Contributor
Joined: Aug 2008
Posts: 2,902
Likes: 21
From: Oak Hill Virginia
For those reading... I posted this in your other thread on the topic...
I've posted this a few times before. Hopefully this will answer your question.
Your rear tires MUST be a MINIMUM of .5" taller than your fronts or your tc/ah will be annoying as hell. It will kick in often and for no apparent reason. The stock fitament provides a 1.1" height difference between fronts and rears.
There are calculators out there; but if I remember correctly (someone correct me if I'm wrong) the formula for calculating the diameter of a tire is:
((Width X Aspect Ratio X 2) / 2540) + Rim Size
So... for example; If you wanted to run a 285/45/19 Tire on a 19" rim your height would be:
((285 X 45 X 2) / 2540) + 19 = ~29.1 Inches
Again; just make sure your rears are AT LEAST .5" higher than the fronts.
Your rear tires MUST be a MINIMUM of .5" taller than your fronts or your tc/ah will be annoying as hell. It will kick in often and for no apparent reason. The stock fitament provides a 1.1" height difference between fronts and rears.
There are calculators out there; but if I remember correctly (someone correct me if I'm wrong) the formula for calculating the diameter of a tire is:
((Width X Aspect Ratio X 2) / 2540) + Rim Size
So... for example; If you wanted to run a 285/45/19 Tire on a 19" rim your height would be:
((285 X 45 X 2) / 2540) + 19 = ~29.1 Inches
Again; just make sure your rears are AT LEAST .5" higher than the fronts.
