I own a 2002 E46 M3 with 18" rims. The finish was damaged in a church car wash (neophyte mistake I know). I can either refinish the 18s or replace with 19"s but would like to hear the pros and cons of the size difference. My car is a cabrio so tracking it is not an option.
Just have yours refinished. THat is the cheapest way. I think supersizing wheels is a bad idea, always.
Thanks MooseheadM5 - I know refinishing is the cheapest way to go but tell me more about why you don't recommend going to a larger wheel? I see the 19" wheels on a lot of M3s and wonder if it's just for the look, or if handling is improved? Logic tells me handling would deteriorate.... is there some benefit to 19s, other than appearance, that I'm missing?
Larger wheels (unless they are forged and expensive) are heavier, and have a higher moment of inertia. Handling, braking, acceleration, and ride quality decrease with wheel diameter (unless they are undersized to begin with like the 14s on an E30.) The giant wheels on later cars is more fashion than anything else.
here's the flip side to the argument: bigger rims = bigger tires which means you have a larger contact patch of rubber for better traction. as we all know, newer cars weigh more each year, and more rubber is needed to compensate for better handing. many people also run staggered 19s, meaning a wider rear tire. on rear wheel drive cars, more traction is needed in the rear, thus a wider tire.
Bigger rims do not automatically equal bigger contact patches. If you run rims that are too large and the sidewall is too short you will normally have less rubber on the road and will only get full contact patch when the car as at very high cornering speeds. Staggered tires add understeer, and cars that need staggered setups are usually very happy to swap ends in a corner under power. 99% of people on the road will not have this problem because they don't drive like me.
