I have 03 track wheels. I want to move my 245/45's that are on the rear now to the front wheels, and then put 265/40's on the back. Does anyone see a problem with doing this? VDC problems?

Thx in advance.

 

You will definitely have problems with that setup. The 245/45/18" tire is 26.7" in diameter. The 265/40/18" is only 26.3" in diameter. The rears can't be shorter than the fronts, they need to be around 0.5" taller.

You would need to go with a 265/45 in the rear. If you stick with those sizes, then you'll also have a problem with the speedometer being inaccurate.

Typically when people up-size their tires, they use a lower profile to keep the overall diameters the same as OEM. For example, the usual step up from the stock 225/45 & 245/45 is to go to a 245/40 & 275/40.

You can check out size combinations with this handy little tool:
http://www.miata.net/garage/tirecalc.html

 

thanks. that is exactly what i was wondering.

Isnt a 275 a bit big to run on a track wheel? I thought 265 was as big as you can go.

 

You can help yourself with similar questions with this calculator: http://www.dakota-truck.net/TIRECALC/tirecalc.html.

 

I've been running 275s on the rear 8.5s for over a year. No wear problems, the Z handles great!

They actually don't look as "pooched" as some people think that they would, and from the rear the car looks like a steam roller!