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I wouldn't recomend getting larger wheels, they lower your horsepower. The car becomes harder to stop, the acceleration is worse, whatever you do, try to keep the overall diameter of the wheel and tire combo, My E32 has 20"x 9, but the tires are 245 40 18, the sidewall is only 2 1/4 inches keeping the same overall diameter
well i know what rb26 is trying to say but getting larger wheels doesn't affect the horepower of the engine. all it really does is make it seem like you have less HP. becasue what it is is that the engine,transmission and final drive gear ratio is designed to get the best performance froma set size out diameter wheel/tire combo. and the bigger the outer diameter is the harder the car has to work to get things moving. however to answer your question i have seen as big as 24's on a 745iL. infact just today i put a set of 20 inch rims on a 745. i would imagine that you could get something close to those sizes on your 645. but i'm kinda with rb26 as far as if you should or not. i think that the factory sizes are big enough. but it's your car you can do waht you want we are just here to give you our input.
lol...yeah I know but information is information no matter how late it comes, maybe the next person thinking about this situation of size could reference this thread for information...but thanks for pointing that out Boy Wonder Lol!
lol...yeah I know but information is information no matter how late it comes, maybe the next person thinking about this situation of size could reference this thread for information...but thanks for pointing that out Boy Wonder Lol!
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