Is that to much for rear wheels? I'm still trying to figure out why I'm getting such crappy gas mileage by just going to 20's. The weight is only 3 lbs more than the fanblades but I'm losing 1-2 mpg with the 20's. It drops awfully fast also if I go by the message centers reading. So if someone adds wheel spacers to the rear wheels Does MPG drop drastically?

 

I wouldn't go lower than 30mm. I think 1 mpg less with 20s isn't THAT horrible of a gas drop off especially if you are doing city driving.

 

That is a lot of stop and go

 

Damn, you went with a 25mm offset wheel? I'd like to see pics of that. Are they 7' wide rims???

And siberian, I don't know who the girl is in your sig but I'm completely smitten. I have a huge problem with dark women and she is sooo dark and georgeous!!!

 

I didn't go with them. They came as the package of 4 wheels and tires I bought. Fits the wheel well perfect to me. They are 20 x 8.5" all the way around.

 

That does look ok actually. I wouldn't go with awider rim than 8.5' w/ that offset though...

 

And that looks like a 30 series tire. shouldn't be that much difference in diameter than stock. You lost 2mpg? I know Shelby's are heavy but damn. Did you recalibrate the computer for the different size wheels?

 

I bet when they told me these were for 05+ that they just put 4 front wheel offsets in 1 package, or these are meant for 99-04. I love them other than the gas mileage.

I don't think the weight is the problem. The 18" fanblades and tires were 50, and the 20's with tires are 53. I did recalibrate the rotations per mile w/ the xcal. But isn't that only for the speedo and mileage? Not MPG?

 

Hell, I'm not really sure but if you're using the car computer for mileage calc's than that is probably the reason. Do you have a GPS?

 

Yes, but GPS doesn't do gas mileage.