Sizes of wheels [Archive] - Bimmerfest - BMW Forums

: Sizes of wheels

06-06-2005, 08:13 PM
Hi there,

Just got my X3 2.5i, it came with the alloy rims:

Style 148, 235/55R17

If I were to changed to the:

Style 114, 235/50R18 (front) and 255/45R18 (rear)

Will I get a significant drop in pickup / acceleration performance?



06-07-2005, 04:04 AM
A handy lil'link below to do some arith on wheel size, etc.
With the diff front/rear, you can't calc Exact, but the "rear to rear" diff
you are wondering about is minimal. Doubt test equip could record
a diff 0-60 speed, etc. Would look "cool" but not impact much, imo.

235/55-17 5.1" 13.6" 27.2" 85.4" 742/mi 60MPH 10000mi N/A
255/45-18 4.5" 13.5" 27.0" 84.9" 746/mi 60MPH 10052mi -0.5%

06-07-2005, 04:44 AM
Thank you very much for the reply.

Do you have any recommendation for tires?

Where I live is summer all year (dry mostly), with a bit of short rain showers. Quieter tires will be good!

Thanks again.

06-07-2005, 12:22 PM
You are welcome, Simon.
No clue on tire brands, but if you don't get some ideas/opins in this thread,
repost your tire brand question in new thread.
I loved Singapore the few times I was there!

06-07-2005, 11:13 PM
Thanks, David.

One of the problems about Singapore is the cars are hugely expensive, and there are very few car specialists / dealers who really know the stuff, including the BMW dealers themselves. The sales person didn't even know if my car had Cruise Control (not that it is important in Singapore)!

06-19-2005, 01:51 AM
I just bought a 19" rim with Pirelli PZero Rosso Asimmetrico 245/45/19, pretty good. Quiet and comfort