I am looking to get the saleen knockoff wheels from mustang tuning, but don't want to use the same size 55 series tire that ford will be using on their 18's. I want to lower the car with the eibach pro kit so that it looks good with a 265 35 18 tire. Will this screw with the computer since it will be shorter height than stock? What about the speedo? Thanks

ps I am sure a tuner(predetor/sct) could adjust for this change but I would rather avoid having to deal with it.

 

you will be going about 6% slower than your speedo reads, so if you are going 60mph, your speedo will tell you you are going about 65. Plus the wheel well gaps will be HUGE, and you will problably have issues with speed bumps because you are lowering the car a little over 1", plus reducing tire hieght by 2 inches, which means you will lose at lease 2" of ground clearance. Lowering will help the wheel gap from the top of the wheel to the fender, but will make the gaps on either side of the wheel really big.

 

How much shorter will it be with a 35 series vs 55? I didn't think about the side gaps. I wish someone had the wheels so I could see what they looked like with either setup.

 

The tire will be close to 2 inches shorter.

 

I found this to be helpful when deciding on wheels.

http://www.1010tires.com/TireSizeCalculato...p?action=submit

 

I WENT FROM 55 TO 40....
LOOKS GREAT...

 

are you sure about the tire being 2" shorter???? I have 18" rims with 285/40's on the rear and wouldn't you know it, they are the same height as the factory 235/55 tires.

 

1.95 inches shorter. The profile is 5% less than yours, and his is also thinner.