20's on 2002 325Ci

Personally, I think you are asking for trouble.

Assuming you have 225/45x17s now, you'll need a 225/30x20 or 235/25x20 to keep the overall diameter at about the same as you currently have.

Your sidewall height will go from just under 4" to about 2.5". The 235's will give a better result from the perspective of gear ratios and speedo accuracy -- although the speedo is slow now, and it will be a bit more slow with the change. The 235s will fit the back okay (if a bit tight), but I'm not sure they will fit on the front.

Troubles with gear ratios notwithstanding, I think you are asking for serious problems with a loss of 1.5" of sidewall.

wrote

How much do they weigh?

Pete

Well, now you're being told that you're nuts.

If you've seen an E46 with even 19" wheels, like the optional M3 wheels, you'd know that even that is really pushing it.

Don't US cars come with wheels? I have always found that stock wheels are just fine with stock suspension and the Bling factor will only make it more desirable to thieves. In the UK insurance premiums rocket skywards when aftermarket wheels are fitted and engine mods are really a no-go unless one purports to be in the "TRADE" with trade insurance - this allows one to drive any piece of gold or crap they have a licence for.

How does an insurance company find out -- and why do they care -- about aftermarket wheels? Do your policies require that you report any modifications to the car? That is not the case in the US.

-- Larry

The lower profile tires this will require seem to not last as long - do they generate higher temps because of less air volume?

Save your cash, retire early.

a.