Trying to beef up my 2008 X5 for the summer

Hey All
Looking to beef up my Rim & Tires on my 2008 X5, I'm thinking either going 20" or 21" on the rims right now. Anyone know how big of a tire I can go without losing any performance at either size rim to give it a more beefy look on the road?
Any sample pics would be helpful
Thanks

i use to have a 2007 x5 4.8i and it had 21" bmw v spoke 239 wheels. they looked really good. if yours is a se then you have to have the side steps and aero kit, if m sport then the performance 21" wheels from bmw look the best i think, i have them on my current x5.
hope im helpful!

Any increase in size or width nearly always means an increase in weight = loss of performance with regards to acceleration, top speed and fuel economy. Braking may be worse too, but that depends on the tire compound.

That said, take a look at the X5 M wheel/tire package for ideas.

- Mike

Going with bigger rims and smaller sidewalls will reduce handling and make your ride harsher. Especially one rough/potholed roads