M3This

18" vs 19" vs 20" vs 21" shouldn't matter as they all can fit on a 5 series (I have even seen 22" wheels)

Its all a matter of tire sizes, for every inch up you go you need to dial down the sidewall. The same offset on a 18" wheel will work on a 19, 20 & 21" wheel as well, you just must adjust tire sizes which is easy using a tire size calculator such as this: http://www.miata.net/garage/tirecalc.html

v_therussian

I would still point out though, that anything 20" and larger will need more careful planning, than smaller sizes. But thanks, you're definitely right

M3This

offset & width control how much the wheel is in towards the suspension or out towards the fender.

wheel diameter and tire diameter control over all diameter (height of wheel) and will effect clearances with turning and suspension compression and droop (up/down movement).

For example ... Im looking at running a 20x9.5 +25 wheel all around with 15mm in the rear ... this would give me affective offsets of 20x9.5 +25 front and 20x9.5 +10 rear, most of you think this will not fit but according to my calculations with rolled fenders all round and some negative camber (-2 up front and -3 in the rear, and 0 toe) it should fit really flush. Basically this will be 37mm closer to the fender in the front and 52mm closer to the fender in the rear. As a result the tire will have to be slightly stretched for clearances.

Since Im running a 20" diameter wheel the goal is to keep the same overall diameter as the stock set up. With the E61 Touring stock sizes are 225/50/17 (overall diameter of: 25.9") and 245/40/18 (overall diameter of: 25.7"). This will result in me running a 245/30/20 Falken 452 as the overall diameter is 25.8" (right in the middle of the stock sizes) and is recommended for a rim size of up to 9" allowing for a slight stretch for extra clearance.

norsecarnut

You are going to rub the heck out of the fender liner when you turn due to the tire arc being considerably wider than stock and wider than mine and my fronts rub at turn. Plus, I think a 9.5" with ET25 is going to be pretty silly from a usability perspective even if the visual perspective is very cool. Of course, with 20" rims, you are not setting it up as a driver's car anyway. I would love to see photos as 20's will be pretty interesting but you won't be going to any of the places I travel, that's for sure.

ja98414

IF YOU READ MY POST, offsets obviously aren't the only thing I asked about . I was asking for general feedback on the issue. Thanks to all of you who tried to help though!

3ve60

hi guys i just got a 2008 535xi...

wanted to get the old m3 rims, 18x8 and it is available in 34,35, and 40 offsets.

which offset would be best? thanks for your help. Lots of talk about 19" and offset but can't find exactly what I need regarding 18x8... thanks!

acuteperformance

BTW, UPS just dropped off a set of the Bilstein B8 Xi shocks. If anyone wants to lower the car and get shocks these are the ones you want.

Michael
Owner
Acute Performance

mazekid15

What am I chopped liver???

I told you I wanted them lol.. My car rides like shit with just HR springs on 19's... This is my only option or pay for KW coilovers and abuse my butt.. No thankss

mazekid15

Just a joke. Michael can you PM me when you get this. Im ready to order them. Thanks

norsecarnut

I would like a stiffer suspension or one with less roll that is NOT lower. I want to retain my clearance for my trips often to roads with less than desirable surface. However, along the 1000-2000 miles before getting there, I'd like a better handling car too.

Would upgraded front or rear sway bars?

My air suspension rear is great for all the crap hauled on trips so for me it's a plus. I just want the best of both worlds somehow.