lookout7

[align=left]I have been told when you go from stock 17 to 18 inch rims you need to change stearing stops. is this true and is there anything else to consider like offset and max width with stock springs[/align]

Mpaint99

I didnt change anything other than my Tuner so the speedo read correct.

TPony

Well, I just switched from 17 to 18x9 on all 4...no issues, other than I already know that my speedo will be a fraction off...

GT Newbie

Did anyone notice a rougher bumpier ride going from 17 to 18 inch wheels?
I was told that might be a problem.............

Stkjock

depends on the sidwall... the 235/50/18 that r a OEM option have tons of sidewall.

When I went to 245/45/18s on the rears I did not notice any difference.
I just went to 265/40's on the rear and I noticed a bit harsher ride.

TPony

Yes, there is a difference. I went with the 255/45/18 which has less sidewall than the stock 17 and less than others. It's a bit bumpier, but still love it.

GT Newbie

Thanks for the info stkjock and tpony- seeing as how the roads are so lousy here in New Jersey, I'll probably just stick with the 17" (lthey're ighter too)- even though I like the look of the 18"'s better.....

Haze28

I went from 235/55/17 to 255/45/18 and 295/45/18rears and I actually think the ride is better now. No other modifications made to the car either.

05gtdriver

I think you're thinking of an old 5.0L Mustang, as they weren't really engineered for tires wider than a 225 to 235 section width. The S197 Mustang can swallow some serious rubber without alterations to the sheet-metal or suspension components. I have owned two different S197 GTs, the first one with the 17" Pirellis, the current car runs the 18" BFGs and while technically they are both 235 section width, the
18" tires are a bit wider(with, of course a shorter side wall as the aspect ratio goes from 55% to 50% from 17" to 18" wheel change from the factory). I notice the car isn't as "mushy" with the 18s and rides slightly rougher, but nothing alarming and the car's handling is improved IMO.

GT Newbie

On many of New Jersey's notoriously poor roads- slightly more "mushy" and less rough is much preferable (except of course to dentists, who just love it when the fillings are jarred out of peoples' teeth)...