I am trying to figure out whether to get 17's or 18's. Does it make much difference in performance (assuming really low profile tires, I know the actual size makes a difference too)? How much? Or is it better to get 16's? I'm thinking of autocrossing, not street purposes. Or is the stock good for auto-x, and get nice looking rims for street.

How/why does it make a difference? Thanks for your help. (I tried to do a search but couldn't find something)

 

I run 17x9's for autoxing and some track use. Going to an 18" would probably have very little advantage. Having a lower profile tire would give you quicker steering response (less tire flex) but I like having a little more sidewall cause you get more feedback and it's easier to predict when you get to the outer edge.

 

I went to 18's. You will definately lose some feedback. The car will look good though. For autox, i'd stick with the 17s.

 

It seems that about 95% of the time, autocrossers go with the smallest diameter, widest wheels that fit the car and which are legal in their class.

The exceptions are generally cars which are somewhat "gearing-challenged" -- where going to a larger diameter tire might give them an extra 3-5 MPH in 2nd gear, or something like that. I don't imagine the Evo would fall into this category; I've yet to hit the rev limiter in 2nd gear on any autocross course I've been on.

 

Thanks for the info. I guess I'll stick to 17s.

vtsnake: just curious about how lower/higher profile helps predictability/feedback. Is it that the low profile is too rigid, and when it breaks at the outer limit it does so with little warning? Thanks again.

 

EXACTLY!

But don't get me wrong, it's not like you'd wanna run a 70 series...

another good thing about 17's vs 18's... tires are a lot less!!!

 

But don't get me wrong, it's not like you'd wanna run a 70 series...

So, going with 17s, what would be the ideal size tires and rims that would fit the Evo? And what profiles are good, and when is it too small?
Hope I'm not asking too many ?s. I appreciate your help.

 

For autocrossing in an SCCA class? Which class are you planning to compete in? How much do you want to spend on tires, and do they need to be streetworthy?

If you are running in Stock class, you are stuck with 17x8 rims. Otherwise go with 17x9.

If you want the ultimate autocross tire, you are looking at the Hoosier A3S03 or A3S04 in 245/40R17, or perhaps the Kumho Ecsta V710 when it becomes available in a size for the Evo. None of these tires are considered streetworthy. The Hoosiers will end up costing you probably $10 - $20 per autocross run.

The Toyo Proxes RA-1 looks like a good compromise if you want a competition tire that can double as a street tire. The 255/40R17 should fit the Evo, but I would make sure they do before ordering them. Expensive, but they are among the longest lasting competition tires around, and they seem to not lose any grip as they wear down.

If you want a street tire which also does well in competition, stick with the OEM 235/45R17 Advan A046 tires.

Lastly, if you are on a tire budget, go with the Falken Azenis Sport in the 245/45R17 size. Not quite as good as the A046, but cheaper and probably will last longer.

 

for maximum width with little modification (fender rolling) you can run 17x9 (35mm offset) with 255/40R17's. That's what I run. If you are doing solo 2, in AS (stock class) you have to run stock width and tire size. In ESP (street prepared) you can run whatever size you want. If you just wanna have fun autoxing, the Kumho Victos will be just fine. But the best tire out is the Hoosier AS03's. They are a lot lighter and have better grip. Downside to them is they only come in 245/40R17's, they cost more, and they don't last as long.

 

Thanks for all the helpful info. I am amazed at the knowledge on this forum. You guys are awesome.