offsets and body damage?

[Departurediver]

It seems like a lot of different offsets are being used. Comptech uses 17x8's with a 42 offset and 18x10's with a 45 offset. It seems like the wheels exceed outside the bottom part of the wheel well. Has anybody experienced any bady damage such as paint chipping from sand, etc. being kicked up on the body? What offsets and sizes are others using and has anyone noticed any problems like this? I'm looking at a front 17x7 with a 38 offset (which keeps the wheel farther in than Comptech's setup) and an 18x9 with a 35 set up (which is just slightly farther in that Comptechs). A larger offset is not available. So I'm trying to get a feel for what works and doesn't. Any input would be appreciated.

 

[s-zero]

You may have your offset numbers confused. The lower the number, the more it will stick out. Comptech sizes are pretty good for their offset and track duty. Yes they will throw a few rocks up at the paint but theres no way around it. I am running 17x8 with 42 offset front and 18x9.5 with 38 offset in the rear and mine stick out too far and rub a little on the fender at the track. The tecnomagnesio 45 offset doesnt rub since it sits in 7mm further towards the brakes. Hope this helps.

 

[RP-Motorsports]

Yes s-zero you are right. The offset number equals the millimeters either + or - from the center of the rim width compared to where the mounting location is. with a 0 (zero) offset, the mounting would be dead center in the rim width, or a "deep dish" style wheel. a 40 offset, would move the mounting location out 40 mm, which would actually "pull" the rim width into the wheel well. a negative - 20 offset, would be 20 mm towards the back of the rim from center, therefore pushing the width of the rim way out, where DTM style fender flares would be needed.

 

[ChrisK]

Just for reference, my car was used with the stock 16/17 rims for years and I still have a lot of rock chips on the painted portion of the rear lower valence directly behind the wheels. I think if you drive the car long enough you will get some paint damage there no matter what rims you are using. When I get mine repainted or have the 02+ valence put on I might put on that clear 3M protective film to protect the paint.

 

[Departurediver]

You may have your offset numbers confused. The lower the number, the more it will stick out. Comptech sizes are pretty good for their offset and track duty. Yes they will throw a few rocks up at the paint but theres no way around it. I am running 17x8 with 42 offset front and 18x9.5 with 38 offset in the rear and mine stick out too far and rub a little on the fender at the track. The tecnomagnesio 45 offset doesnt rub since it sits in 7mm further towards the brakes. Hope this helps.

Thanks. When I was talking about distance, I was taking into account the different width of the wheels too. So a 17x8 with a 42 offset will be farther out than a 17x7 with a 38 offset. But the 18x9 with the 35 offset is virtually identical to an 18x10 with a 45 offset (if I did my math right). So you're 18x9.5's with the 35 rub? What size tire are you using? Did you lower your car at all? ... and thanks for the input everyone.

 

[s-zero]

Actually, a 17x8 and a 17x7 with the same offset will put the wheel at the exact same position if you mount the same size tire on it. If the offset is different then the wheel position will be different. I am running 265/35/18 rears and am running tein ra's. They lowered the car almost 2 inches stock so i brought them back up to a 1 1/4" drop and they dont rub, even at the track with this setup but they do stick out a little bit. The top edge of the tire lines up exactly with the fender above it. I would recomment an offset of 43 in the rear and 40 front and i dont think you would have any rubbing problems even with a 2" drop.