[mopar_man]

Originally Posted by Chromenut

I just went to a show two weekends ago and met a guy that had beautiful 18's on his, and he had to shave his calipers for them to fit, and you could barely fit a piece of paper between the wheel and the caliper![

Are you sure he didn't upgrade his brakes? Don't the factory GT's come with 16" wheels?

Originally Posted by Chromenut

In my picture below, you can stack three quarters between the top of my tire and the bottom of the spring seat on the front struts. Thats right at 3mm clearance. Probably gets less when I'm running hard and heating up the tires, but that's as close as I want to come.

That distance doesn't change. Your strut is bolted to the knuckle. Had you measured that distance before you lowered it, you'd find that there wouldn't be any difference. If you don't believe me, get a flashlight out and have somebody bounce the suspension while you observe in the wheel gap.

Originally Posted by Chromenut

Backside spacing is from the rim to the center of the mounting surface at the middle of the wheel. Offset is either a positive or negative number, and this refers to the mounting surface to the centerline of the wheel. So if you cut that wheel in half right down the middle vertically, how far in or out would the mounting surface be.

Backspacing and offset are different. To measure backspacing, lay a straight edge across the back of the wheel and measure to the hub face. This number is always positive. Offset is from the middle of the wheel to the hub face, which can be positive or negative.