I'm looking into getting ssr comps in a 17"x8.5" trim. Is anyone else running this size on there 8? I'd like to know what offset I should be getting that would clear the caliper just enough but not over doing it.

Also what tire and size should I look into. I'd like some lightweight high or max performance tires that can still handle some rain.

thanks in advanced

 

exactly my situation... the only thing thats turning me off is that i have 18s so going to 17s will five me false mileage.

denward

 

I like my BFG KDW's, cheap too!

 

only if you don't keep the overall wheel/tire diameter the same as the stock diameter.

I was thinking of going with SSR Comp 17's also, but I want to keep diameters the same. I don't know if the added sidewall will negatively affect handling and the weight reduction of going with 17's though.

I also like the KDW2's but mine are fairly noisy after 20k miles, but I do have a slightly bent rim.

 

i also want to 17 for gearing also. so unless someone makes a speedo healer for the rx8, i have to deal with inaccurate speedo and odo.

denward

 

The taller sidewall will give a smoother, less jarring ride. It will be smoother steering over less than ideal surfaces; less "jolt" back through the steering wheel. A taller sidewall tire will also be less susceptible to tire nibble over grooved surfaces such as concrete freeways. The sidewalls actually absorb shock and vibration to a degree. Low sidewalls give super responsive steering, but amplify everything back through the steering wheel; you can practically feel paint stripes when you drive over them.

Smaller diameter rims will spin up quicker; in addition to being lighter, the closer to center wheel mass is, the faster it can accelerate. The only downside if you want to call it that, is you won't have the current trendy "stuff the wheel wells as much as possible with rims" look. You'll have more tire visible than is trendy-correct, but your car will ride smoother, handle smoother, and accelerate quicker. I was seriously considering going with 17's but I didn't want to deal with the speedometer/odometer readings issue. There's no way to recalibrate the RX8's speedo; it can only be done at the factory by the engineers and they aren't offering that service. I wasn't so much concerned about the mph...I can mentally adjust for that when driving, but I was concerned about the effect it would have on the odometer and miles driven. I didn't want it to appear I had driven the car more miles than I actually had.

I have the KDW2's as well, great tire... noise doesn't bother me especially since they're quieter than the stock tires I replaced.

 

so would it be a bad idea going with 50 series tires? Will the handling decrease dramatically?

Also what offset is recommended for a 17x8.5 wheel?

 

Check out Goodwin Racing's site They're running Enkie RPF-01 wheels, 45mm offset, 18x9.5 with 275 Azenis on their shop RX-8 with no rubbing issues. Assuming that the 17" wheel you're considering will fit over the brakes, you should be able to get away with a similar offset. 275 is a lot of tire, so a 245 or a 255 should fit with room to spare.

As for tire size, a 255/40/17 will have an excellent choice of tires. I believe it makes the speedo read a little less than 3mph fast (see the miata.net tire size calculator).

 

Handling will be fine; just a little less "darty". Low profile tires give very quick response because there's virtually no sidewall flex; it also makes them less forgiving for everyday driving. Depends on what you want the most; ultra tight steering response, or a comfortable daily driver with excellent steering response.

Don't know what the offset should be.