Revelation Z28

iTrader: (10)

is there any effect of having the wider and taller rims on my car now besides the very little extra rotating weight? like my gear ratio changing or anything. i have 4.10s now, and it seems like my 1st gear lasts about .5-1 sec longer now.

chaman

iTrader: (5)

You can have the same wheel/tire ratio even on 17's. The effect would be minimal IMO. If you go wider you could have more tracking.

Revelation Z28

iTrader: (10)

ok. well ive noticed way better tracking with 275s in the front. i heard that putting a bigger diameter rim on will lower your rear gear ratio some, but not much. i was hoping for a little bit since my speedometer is still uncorrected, and id like to have a little less than 4.10.

MannyZ28

iTrader: (1)

Your gear ratio only changes with tire diameter. In the end, it's the tire that you put on a wheel that gives you the final overall diameter. A 245/50/16 has the same tire diameter (25.6") as a 275/40/17 and a 315/35/17 and also a 275/35/18, that because the shorter sidewall makes up for the increase in wheel size. Now if you put a tire taller than the stock 25.6" then you are starting to change your gear ratio.

Wider tires in the front will help braking performance. Also, since you are going with the 275/40/17s you should have a bit better handling due to the added width of the tire and also due to the reduced tire sidewall height and increased stiffness of the sidewall. Remember that the middle number is a ratio. On a 245/50/16, the 50 indicates that the sidewall height is 50% of the width of the tire. On a 275/40/17, the sidewall height is 40% of the width of the tire.

So, in a nutshell, as long as the tire diameter stays the same as stock, you don't change the gear ratio and you also don't throw off your speedo.

Manny