clauwrx

changing the original 215/45/17 tyres from a 2007 WRX with 215/35/17 tyres will help gear ratio in a better way ?

how about the transmission...I will lower the stress on the transmission doing this mod ?

i know that the speddo will read more than real speed, but that isn't a problem

thanks

corradoboy

This isn't a mod The only benefit may be less movement in the tire wall resulting in a sharper steering feel, but this will also reduce ride comfort, and the car will break away a little more suddenly with less warning if you get things wrong in a fast corner. The tires will probably be more expensive too. Your speedo will be 6.9% out (60 on speedo = 55.9 actual). 235/40/17's will balance out your speedo and give a wider tread, resulting in more grip and a similar feel and breakaway as the profile will be almost identical. Not much more expensive either.

If you're getting new rubber, look at Uniroyal Rainsport 2

dunx

iTrader: (3)

Car will accelerate quicker due to lower gearing.

All the rest of Dave's comment apply.

dunx

iscooby

Can you explain this??

dunx

iTrader: (3)

What, that a smaller rolling radius means shorter gearing = faster acceleration ?

HTH

dunx

P.S. 7% lower gearing == 7% more power !

i.e. 400 bhp on std == 428 bhp on low profile.

iscooby

I'm off to get some 13" wheels then !

clauwrx

07 WRX has 3.70 final drive ration with stock 215/45/17

if i change the tyres with 215/40/17 or even 215/35/17 what will be the final drive ration ?

again, i'm doing this to prevent more stress on the transmission and to have a fast car for small distance (400m)

thanks