Are 18" Wheels with 40 Profile Tyres a much harder ride than 17" with 45 Profile Tyres ? Is it a worthwhile performance improvement.

 

Performance improvement.......no, just the opposite

 

Slightly stiffer ride. Your average driver, such as me ain't never gonna get that close to the performance limit of 17's or 18's so telling the two apart for outright performance shouldn't be an issue - certainly not on the public road anyway

 

If you are changing OE 17" rims (about 12kg) for a decent low weight 18" rim (ie a PFF7 weighs about 8kg) then the ride can actually improve. Tyre choice makes a difference as well, something like a Goodyear F1 gives a much better ride than the OE RE040s. I went from OE 17"/RE040 to 18" PFF7/F1 on my 03STi and the improvement was very noticeable (and welcome).

 

I thought the bigger the wheel, the worse your acceleration gets?

 

I have 17's 18's and 19'' and i would say
look wise 19's
cost wise 17's cheaper tyres
All round 18's
18's look good and if they are light better than 17's

 

also depends on your car; Prodrives' wheel upgrade for the classic was 17 and for the newage 18. Don't go over 17 on a classic or 18 on a newage. If in doubt try and have a drive of one with larger wheels fitted.

 

My new-age is on 19"'s with 235/35 Toyo R888's and the grip is phenomenal but they are ultralight wheels, and weigh less than oe STI wheels too !

DunxC

Don't go too big on a classic tho'.