[Guest]

Hi everyone,

I just recently got into an accident which caused me to be pushed into the curb blowing out my front tire, destroying my right sideskirt, and literally mauling my wheels to shreds. These wheels were already on the car, so i'm not much disheartened, however, i'm planning on changing all four to SSR GT3 with Kumho Ecsta Supras. As my previous wheels were 17", and I have now decided to get 18" wheels, can anyone knowledgable about these things (wheel fitment, offset, etc) tell me a good 18" setup regarding offset, tire size, etc. Thanks everyone, I know Andi knows a great deal about this topic because of his autocrossing =).

P.S. Should I get the fenders rolled as the car will have to go to the shop to get the sideskirt replaced eitherway?

 

[Andi]

Hi everyone,

I just recently got into an accident which caused me to be pushed into the curb blowing out my front tire, destroying my right sideskirt, and literally mauling my wheels to shreds. These wheels were already on the car, so i'm not much disheartened, however, i'm planning on changing all four to SSR GT3 with Kumho Ecsta Supras. As my previous wheels were 17", and I have now decided to get 18" wheels, can anyone knowledgable about these things (wheel fitment, offset, etc) tell me a good 18" setup regarding offset, tire size, etc. Thanks everyone, I know Andi knows a great deal about this topic because of his autocrossing =).

P.S. Should I get the fenders rolled as the car will have to go to the shop to get the sideskirt replaced eitherway?

Well it really depends on what sizes the wheels and tires are available in. My favorite 18" sizes would be 18x9.5 (~45mm offset) with 265/35-18 and 18x11 (~47-50mm offset) with 295/35-18's.

My guess is that the wheels you're getting will be 18x9 and 18x10 since that's the most common 18" fitment. For those sizes, 245/40-18 and 275/35-18 will be fine. As would 265/35-18 and 275/35-18 if you want less understeer....

Andi

 

[2JZFAN]

I'm going to be buying some rare 19's and would like to know the correct numbers. Largest size available is 19x10 Rears and it goes down from there 19x9.5, 19x9, etc etc..

Thanks,

 

[Guest]

Re: Re: New Wheels and Tire Fitment

Well it really depends on what sizes the wheels and tires are available in. My favorite 18" sizes would be 18x9.5 (~45mm offset) with 265/35-18 and 18x11 (~47-50mm offset) with 295/35-18's.

My guess is that the wheels you're getting will be 18x9 and 18x10 since that's the most common 18" fitment. For those sizes, 245/40-18 and 275/35-18 will be fine. As would 265/35-18 and 275/35-18 if you want less understeer....

Andi

I run 255/35 on the front 18x9 (41 offset) and 285/30 on the rear 18x10 (45 offset). 265/35 and 295/30 require perfect offsets not rub. I believe they need to be 45 and 50 respectively.

For a street setup, a 30 profile in the rear (instead of the 35 Andi recommended) will keep your stock overall tire height (25") closer than a 35 and hence not throw your speedo off at all likt the 35 will. BTW, Steve Jarvis is pretty much the authority on this if you can find him.

 

[SinfulMKIV]

Hi everyone,

I just recently got into an accident which caused me to be pushed into the curb blowing out my front tire, destroying my right sideskirt, and literally mauling my wheels to shreds. These wheels were already on the car, so i'm not much disheartened, however, i'm planning on changing all four to SSR GT3 with Kumho Ecsta Supras. As my previous wheels were 17", and I have now decided to get 18" wheels, can anyone knowledgable about these things (wheel fitment, offset, etc) tell me a good 18" setup regarding offset, tire size, etc. Thanks everyone, I know Andi knows a great deal about this topic because of his autocrossing =).

P.S. Should I get the fenders rolled as the car will have to go to the shop to get the sideskirt replaced eitherway?

Ok the Kumho's suck.. i have those tires on my rear right now.. 18 inch too and they suck high end.. 120 + they are not stable at all.. i would not recommend getting these tires..

Before these i had Bridgestone pole positions and then pirrelli P-Zeros.. those were great.. pole positions a little better cause they did not wear AS fast as the p-zeros..

I would say spend the extra cheese and get good tires..

only reason i got the cheap ass kumhos is cause i was in a hurry to change out the rear tires and i was out of a job at the time.. stupid me.. learned a lesson tho.

 

[Guest]

Kumhos

So, the Kumhos aren't great eh? I went by the price and the user rating at TireRack.com. Thanks for the info...anyone else have this problem?

 

[Steve Jarvis]

The largest you can run on the rear is a 10.5" with a 55mm offset. I run this with a 295/30R18.

As far as Kumho's go I use them on the roadcourses at two of the tracks I run on, I exceed 150mph (radar verified) and they are perfectly stable.

Later, Steve

 

[yasir]

Hey Steve many thanks on helping and guiding me thru on my purchasing of the right size wheels and the tires without any rubbing. Just to let other members know i'm running 265/35/18 on 18x9.5 (45mm ) and rear 295/30/18 on18x10.5 (57mm) offset.
However Steve i agree with u that the perfect offset would b 50mm upfront and 55mm rear.
Regards. Yasir: Just can't D

 

[2JZFAN]

yasir what wheels do you have? Also what makes 50 front and 55 rear the best offset? What does the offset do and what do higher numbers mean?

 

[yasir]

Offset is the the distance of the center part (mounting part) of the wheel that comes in contact with the hub. The lower the # the more outside the wheel moves.The stock toyota offset is 50mm. If u buy a wheel that has a 40mm offset i think the biggest tire would b 275/285 that u can put on without having to roll the fenders.The higher the # and the more indide the wheel moves and it might touch your inner fender wall. Go to www.tirerack.com and read about the offsets.
Regards. Yasir

 

[2JZFAN]

Can someone explain the tire size things. (ex. 255/40YR19 Bridgestone S-03) what do each of the numbers mean, and how can I find the right tire for my wheel? I am going 19x10 rear and 19x9.5 front.

 

[Guest]

I've had my Kumhos over 150 mph and the car was very stable. Look at suspension or inflation pressure if you felt instability. Jeff

 

[FYRARMS]

Suprascene.com:

Take a P285/35ZR18 tire.

P = passenger tire

285= width of tread in millimeters

35= aspect ratio (35% of width is sidewall height)

ZR= speed rating

18= size of wheel diameter in inches

offset= distance in millimeters between imaginary center of wheel and the mounting surface

backspace= measurement in inches from mounting surface to innermost side (back) of wheel

Now go impress your friends!

 

[2JZFAN]

lol thanks got it, but what impact do sidewalls make on the tires? Someone was concerned about sidewalls in another thread.

 

[FYRARMS]

Well, sidewalls play an important role in how the car will handle different situations. In a nutshell, for drag race use you want a tire with a taller sidewall. 15", 16" slicks give the most traction, and the sidewall will absorb a lot of torque. Watch a race slick "wrinkle" on launch. A shorter sidewall has less "give", and is better suited for road course or autocross racing, where you don't want a lot of sidewall deflection. In drag race use, an 18" or 19" tire will not absorb much torque in the sidewall, and usually goes up in smoke...

There are some cases where a taller sidewall helps handling, but that's a different lengthy discussion. For example, I owned a 1989 Turbo Trans Am Indy Pace Car with stock suspension. The car ran 11's, and handled VERY well. However, I turned faster lap times with 16" Yokohama A-008RS tires than I did with 17" versions. This was probably due to the vehicle's heavy weight and stock suspension. Go figure!

 

[2JZFAN]

So the sidewalls aren't rated but are based on the size of the tire. If I have 17's I'll get more power to the wheels because the sidewalls are smaller and if I have 19's the wheels will spin more than the power i get to the ground.

 

[FYRARMS]

You almost got it, man!

Actually, 17" wheels will have a BIGGER sidewall, which is better for drag racing than 19" wheels.

Picture a 1970 Chevelle with big-ass 15" slicks. Now picture a 2002 Cadillac Escalade with 22" Michelins and like NO sidewall. The 15" wheel/tire combo might be the same overall height as the 22" combo, but more of the height is in rubber and not in metal. Get it? More rubber between the wheel rim and the road means better power transfer when launching the car. This is why John Force does not use 19" wheels w/30-series rubber on his funny car.

 

[2JZFAN]

Got ya so I'll be betting P-Zeros on my 19's and A032's on my stockers. thanks alot man.