GSXRAWD

I just picked up a set of wheels that are 18x8.5" and 18x9.5". what is the biggest tires I can fit on them?
also any suggestion on tires?

Manaray

I would recommend the following:

18" x 8.5" = 245/40-18
Speedo Error: 0.0171% compared to stock 16's
Speedo Error: 1.5389% compared to stock 17's

18" x 9.5" = 275/35-18
Speedo Error: 0.6423% compared to stock 16's
Speedo Error: 0.9949% compared to stock 17's

The Speedo Error going from Stock 16's to Stock 17's is 1.6210% so those 18" size won't affect your Speedometer reading.

For comparison, I have a 245/35-20 on the front (which is a 5.6272% Speedo Error) and I don't even notice it...

As far as tire brands, well that's somewhat of a Holy War. Some people believe in one brand and hate others and someone else will have exact opposite results/feelings.

Personally, I don't like Pirellis. I think they're over priced and they don't last for *****. They're traction is nothing special compared to other tires I've tried.

My first picks are usually Nitto or Toyo. Also, if you want to save some money, I like the Kumho's. My buddy has a set on his 3000GT VR4 (All wheel drive, Twin Turbo @ approx. 320HP) and he loves 'em (he's also a professional stunt driver so he knows a few things about tire performance! He also dislikes Pirellis... )

Some prices:
245/40-18
---------
Kumho ECSTA Supra 712 - $132/ea
Nitto NT555 Extreme - $156/ea
Toyo FZ4 - $184/ea
Toyo T1-S - $210/ea

275/35-18
---------
Kumho ECSTA Supra 712 - $164/ea
Nitto NT555 Extreme - $228/ea
Toyo FZ4 - $204/ea
Toyo T1-S - $255/ea

KNKGS400

can we put 245/40/17 on our stock gs wheels has anyone try this, just wondering? also i am considering 18s also, so if i stay 245/40/18f and 275/35/18 r would that affect my nav, cause if i recall l-tuned rear is 265/35/18? i think

GS4Will

K,

275/35/18 would be fine, nothing will be affected.

245/40/17- too small in overall diameter, too few tyres to choose.

BadBtsz4u

soI cant go 18x7.I should go 18x8.5.My only reason for wanting to go smaller width is wheel availability.so 18x8.5 all around or no(for rims)

BadBtsz4u

soI cant go 18x7.I should go 18x8.5.My only reason for wanting to go smaller width is wheel availability.so 18x8.5 all around or no(for rims)