Bumpnz

I recently came into some extra cash, and I have been wanting to get a new set of rims and tires for my car. I have been brousing lots of different threads on the subject, along with checking out web sites. My brain is overflowing with information and a handful of it is conflicting information.

Currently my car has the standard setup for a '94 Z-28, 245/50 16. I want to switch to an 18" rim and use the same size tire, at all four corners. I might be swayed into putting a larger width tire on the rear. I don't want to modify my car to get a rim/tire combination to fit. If I use a 18" x 9.5" rim, what offset is best? I don't want my tires sticking out past the fenders. What is the largest (width) tire I can put on the front and not have clearence problems when I turn? Same goes for the back, less the turning part.

This site is full of very knowledgeable and is an invaluable resorce for information, glad the site exists.

Chris@Tires.com

If it were mine, I'd go with an 18x9.5 all around with a 275/35R18 tire so you can still rotate.

What style of wheel are you looking for?

Injuneer

For a 9.5" wide wheel, you will be looking at offsets in the range of 38mm to 56mm. The 38mm offset will put the wheel almost flush with the outside edge of the front fender, and might cause some rubbing on the fender lip. A 56mm offset will put the wheel about 0.7" deeper in the wheel well, and will center it to avoid rubbing of the tire on either side. I had some OZ Monte Carlo 17x9.5's with a 49mm offset, and they looked decent.

In the back, the wider fender and "no turning" makes the choice of offset/backspace more forgiving, so if you want the same wheels on all four corners, its the front that will dictate the offset required, and the size of the tire that avoids rubbing.