I need help picking the tire sizes for the 18" Work CR Kai wheels I've ordered from the Z1's group buy. The sizes of the rims are 18x8.5 +20 and 18x9.5 +20. I'm looking for the optimal tire setup with the widest possible section width, no rubbing issues if lowered around 1 inch, and won't give me trouble with VDC. I've been playing around with the tire calcuator on discounttire.com and would like to hear from any of you that have expeirence running similar setups.

I know that 245/40/18 and 275/40/18 are the recommed tire sizes for 8.5 and 9.5 inch rims but I was considering some of the following tire combos:

255/40 and 285/40

255/35 and 285/35

265/35 and 295/35

Any experience or input will be appriciated.

 

Anyone?

 

im runnign a 245/35 front and a 285/30 rear and my tcs works fine.

 

It really depends what you want. If you want the widest set up, you can go with 255-40-18 (26.1 inch) in the front and 285-40-18 (26.9 inch) in the rear w/o any issues with VDC and you should not have any rubbing issue even if you lower it 1 inch but you will lose some performance due to the diameters of the tires. Your obdometer will be off by little. You actually be going faster that what your obdometer is reading.

265-35-18 (25.3 inches) and 295-35-18 (26.1) will be a set up you are looking for with widest section width w/o having any issues VDC but the tires are too wide for the wheels and you may have rubbing issue if you lower the car. In this case, you obdometer will be off by a little also. You will be going slower than what your obdometer is reading. You may gain a little performance due to smaller diameter of the tires.

Last but not least. With 255-35-18 (25 inch) and 285-35-18 (26 inch), you are on a border line with having an issue VDC but in my opinion , you will be OK. I read somewhere in the forum that if your tire diameter is off by an (+,-) 1 inch or more than stock spec, you will have an issue with VDC but there are members in the forum who are running 275-30-19 in the rear which is 25.6 inches and they are not having issues with VDC except when turning corners. Thats 1.1 inches smaller than stock spec. As for lowering, you will not have an issue. You will gain some performance due to smaller diameter of the tires. Your car will be going slower than what your obdometer is reading.

Stock specs are 25.7 inches in the front and 26.7 inches in the rear.

My recomendation is go with first option 255-40-18 in the front and 285-40-18 if don't mind loosing little performance.

Just my opinion.

 

Thanks for the advice. I guess I would prefer to run the 265/35 and 295/35, but as you stated the tires might be too large for the rims. I remember reading some posts from members running 295's on 9.5" rims so I'm wondering if it's doable. I definelty don't want to loose performace or turn-in feel by running too tall of a tire.

I also like the 255/35 and 285/35 but I agree that it would be boardline with the VDC, even tho the difference in tire diameters from stock is less than 1". If anyone out there has run any of these sizes please chime in.

 

You, your car, and your VDC will be fine with your prefered 265/35 & 295/35's!

We run up to a 325 or 315/30/18 on a Nismo 9.5" wheel, and a 285/30/18 on the 8.5 fronts on the track and on the street...No PROBLEMS at all.

 

Awsome, exactly what I wanted to hear. Thanks. Which tires do you use?

 

Name it, and if that manufacturer makes it in our sizes (rare) we have probably tried them. Perrelli, Michellin pilot (sport and cup), Kumho, Hoosier, etc.

 

From what I've read these tire manufacturers recommend a 9" rim width for the 265 and a 10" rim width for the 295 profiles. These will really fit on 8.5" and 9.5" rims without problems?

 

Man,......we do it all the time.. ....on lowered cars!. Here is a pick of a 315/30/18 on a 9.5" Nismo rear wheel and one of our Perelli Corsa's (same size) that we put on vision619's car.....Like I said NO PROBLEMS!!

 

If the wheel recommend tire:245/40/18, and i put on tire: 245/45/18...

anyone know what will happen?? like any rubbing issue??

Thanks....

 

Lowered, or stock hight? It prolly will be fine.