I'm having some issues with getting tire combos to match up. I have a 2001 with magnetic ride so I have to keep .5" to 1.5" rake and that's where te problem is. I can't get te tires I want and stay with in those specs. Can I go over just a lil bit say .5" or will it seriously cause problems.

 

.5" seems to be the bottom limit where it becomes a hit or miss... Some people have issues and some people don't. Personally, I wouldn't take the chance.
What tires are you looking at?

PS. It's not magnetic ride that causes an issue, it's the traction control/active handling. You have a 2001, and therefore don't even have magnetic ride.

 

Magnetic Ride wasn't available until 2003. You may have F45 (RTD) with the select button for ride control, but that is not your issue. You need to keep the overall tire diameter as close to 1" taller in the rear as you can to prevent active handling/traction control errors. I would not personally try .5" difference, that's at the limit. Some have done it with success, or at least intermittent success.

 

Why are you having problems finding tires with the factory stagger? Should be plenty of brands to chose from. Aftermarket wheels?

 

Lol your right. I know it's RTD but for some reason I have a real bad habit of calling it magnetic ride.
I meant going .5" over the 1.5" max

 

You're right, the total 2" difference will cause you lots of problems. You're going to have to adjust something in your size preference.

 

What size rims do you have and what tires are you looking at? If we knew this we could help you.

 

I have Cray scorpions 19x9/20x10.5

 

Wanting to get nitto NT05R 315/35/20 but can't get a front tire in the right size to keep te rake right

 

Lol I wouldn't have a problem, but with over 800rwhp my choices are limited

 

Could I run a 295 on a 9" wide wheel

 

I know what you're trying to accomplish, but I'd like to try and clarify something here. The "rake" you refer to is primarily a ride height adjustment, where the rear of the car is slightly higher that the front, to keep more air pressing on the hood of the car, rather than allowing air under the car, and causing "lift".

The difference in tire diameters is to keep the traction control/active handling systems happy. The car's computer "reads" the wheel speeds, and expects to see a predetermined difference between the front and rear tires. If this ratio is exceeded, generally with rear tires that are "too small" compared to the front, the car interprets this as wheelspin, and acts accordingly, in order to eliminate it.

 

thats what im having issues with. the 315/35/20 NT05R nittos are 28.7" in diameter and a plain nto5 for the front in a 275/35/19 is 26.6" in diameter, which results in the rear tires being 2.2" in diameter taller so that will cause me problems correct. however i can get a Nitto invo in a 285/35/19 which is 26.9" diameter and would be a 1.8" difference between the rear tires. Or i can get a BFGOODRICH KDW2 in 295/35/19
with a 27.1" diameter and that will drop down to a 1.6" diameter difference with the rears being taller. regardless they are all over the 1.5" max.

 

I don't care what tire you put on a 20" wheel with over 800rwhp traction will be
You would be much better going back to the 18" wheel to gain some sidewall.

 

This is true but I like my twinkies in the back . Just trying to make the best out of what I have. Eventually I will get the wheels widened to 12" In the rear so i can run 345's and 10" I'm the front. Also I like being different than other people, so stock size wheels are a no go

 

If you have a rear tire that is 0.5" larger (or more) than the front you should be fine.

A friend of mine is running the following and had not reported any issues.

285/30/19 = 25.8"
305/30/19 = 26.3"
Rear tire is 0.5" larger in diameter.

Another friend of mine is running a 275/35/18 front, and a 345/30/19.
He has never had an issue with Active handling or traction control he reports.

275/35/18 - 25.6"
345/30/19 - 27.2"
Rear tire is 1.6" larger in diameter.

Its always best/safer to try to stay close to Stock OEM numbers though:
Stock Coupe/Vert = 1.0" larger rear tire
Stock Z06 = 0.7" larger rear tire.

Its been my belief that you will run into issues with TC/Active handling if your rear tire diameter is close to, or smaller than your front tire diameter.

Your car knows the diameters of your tires, and expects that your rear tire will turn less rotations than your front tire. If it senses that your rear tire is turning more rotations than your front tire it thinks your "spinning" and turns on TC.

I have always wondered about how much larger you can go on the rear tire though before it effects your AC / TC. My friends car above at 1.6" larger rear tire does not seem to have any issues. How large a rear tire can you go before Issues ? That is the question.

Toque

 

Thanks Toque,
That's what I was wanting to hear

Do you think I will be fine putting a 295 on a 9" wide wheel

 

Look at the tire specifications on the OEM manufacturers web site to see if that tire is recommended for a 9" wheel. Thats the best place to look.

Ask "rdline" about what tire sizes he runs. They look rather large...

Toque