18x9 +48 OZ Ultraleggera and 235/40-18s?

[assman]

You guys seem to know what your talking about so rather then start a new thread I will ask you guys.

I am considering going to a 17X8.5 or 17x9.5 for lighter weight and better performance on the 1/4 and autoX.

If I went with either option
1. what tire size would be best for each
2. what would the offset have to be?

Thanks

 

[udontknowjack]

You guys seem to know what your talking about so rather then start a new thread I will ask you guys.

I am considering going to a 17X8.5 or 17x9.5 for lighter weight and better performance on the 1/4 and autoX.

If I went with either option
1. what tire size would be best for each
2. what would the offset have to be?

Thanks

why do u want that wide for autox? i think 17x8 45-50 offset is all you need... what kinda suspension r u running...i ran 245/45/17 on 17x8 50 offset v710 kumho....i doubt can u run any wide tires....

 

[assman]

I thought wider would be better? Am I wrong? Suspension is stock for now but I plan on Cobb sways and maybe new springs and coil overs for this spring.

 

[udontknowjack]

I thought wider would be better? Am I wrong? Suspension is stock for now but I plan on Cobb sways and maybe new springs and coil overs for this spring.

wrong....wider only if u want wider tires....lower offset is better than wider wheels...cuz wider wheels usually mean heavier...unless u r going with fender flares....8 is as wide as u need....and 45 would be nice offset...but then you will have to have ur rear fender trim or roll...

 

[photoracer]

I'd vote for 17" over 16" for autocross. Tests have shown that 17" are faster with the tires available than 16" from my experience, where as 18" have no real speed advantage over 17".
Reason I'm saying that is I'm going to go back to Auto-X next year after a long absence due to road racing in SCCA. One thing I have of from my Mustang Cobra Touring car is lots of 17" wheels of 8-9" width which have 5x114.3 stud spacing. My best are a set of 16 pound SSR Intergral A2 in 17x9 with +35mm offset. That will clear the suspension but may stick out some. Plan on using them either in DSP or STU with 255/40-17s on them. I can still buy Kumhos at cost for myself if I need them. I do have a set of 245/40-18 BFG R1s I can mount on my Kosei K3 street wheels. Was planning on using them for when I'm doing HPDE instructing at Summit Point.