I know when we put larger rims on our cars it slows them down, I would love to put some nice 18s on my car but was wondering how much of a performance decrease I should expect.

 

None, if you get some that are about 3-5 lbs lighter than stock. Jens, said the stock wheels weight 26lbs each. The 3-5 lbs is just a "rough" rule, since all wheels are constructed differently.

 

Ok, I heard it was not so much the weight but the height of the rim. Saving weight would be great too.

 

Height has very little to do with it....


it is basic physics basically....

wheels are round the centrifical force on heaver wheels will decrease the rotations it would make if it had the same amount of power to it....therefore with light wheels in the 15-20 range 18"s you still have the same inertia you have as you did in 17"s, less inertia you have the better off you are

hope this helps....go find some hot 18's now ,
Dantes

 

18'' rims with some 40 series tires are about the same setup as the stock 17's with the 50's... so i don't think there should be a performance issue. or i could be wrong

 

I know that my 18" rims weigh about 14.5 pounds...I'm not entirely sure what my tires weigh though...it's almost time for new tires, I'll be sure to check one and post it here...
btw: my performance was improved by the larger rims....

 

Your performance was improved by better gripping tires and lighter rims. Large rims means large tires which typically means better grip, cornering...

It's the lightness of your rims that makes the big difference.