R17 to R18?

Already swapped out the base suspension for the Performance Suspension but still have the OEM R17 wheels. Tires are worn enough that it is about time for new ones and I thought I would go with a R18 rim with more width and stagger. What cracks my head is all the talk about offsets and other mods that I would need to do that. Can anyone help me out and explain what I would need in addition to the wheels to swap in style 287s, 193s, or 195s?

Have you read the articles on tirerack.com about offset, stagger and such? Start there.

Stagger is easy. Hub-centric spacers aren't generally recommended, but can be done.

I had no idea what this thread was about. Never heard of wheel size referred to as Rx either. Spacers may cause vibration at high speed, even if they are hubcentric and over 11mm thick.

Originally Posted by EYE4SPEED

I had no idea what this thread was about. Never heard of wheel size referred to as Rx either. Spacers may cause vibration at high speed, even if they are hubcentric and over 11mm thick.

Sorry to be unclear. Current setup is Performance Suspension with stock 17 inch rims. I want to go to an 18 inch rim but also with an 18 inch rim with asymmetric width tires, wider in the rear than the front. Style 287s would be my target, but the general question is whether I can take the new rims and bolt them directly on the hubs as they are now, or whether I need to add any spacers to permit wheel clearance. The drop from the base suspension to the Performance Suspension was modest - maybe 1/2 inch - and I would go with the OEM diameter tire - 225/45s on the front and 255/35s on the back (I think that's right).

Originally Posted by tonyspumoni

Sorry to be unclear. Current setup is Performance Suspension with stock 17 inch rims. I want to go to an 18 inch rim but also with an 18 inch rim with asymmetric width tires, wider in the rear than the front. Style 287s would be my target, but the general question is whether I can take the new rims and bolt them directly on the hubs as they are now, or whether I need to add any spacers to permit wheel clearance. The drop from the base suspension to the Performance Suspension was modest - maybe 1/2 inch - and I would go with the OEM diameter tire - 225/45s on the front and 255/35s on the back (I think that's right).

Yes, is the answer to your question - no modification required, but check your tire sizes. If you want the wheels more "flush" with your fenders add spacers.

It all depends on how "flush" you want your wheels to look with your fender. If your wheels are the same width you will need to run a bigger spacer in back then in the front to really get that staggered look. If you are looking for a "flush" look the spacer size will depend on your wheel offset. Any spacer over 5mm I recommend hubcentric otherwise your hub has enough lip to run 3mm to 5mm and still be hubcentric. VAC Motorsports sells some of the nicest/best spacers on the market IMO - talk to Chris Bull he'll take good car of you.

Talk to Tirerack they have what you need, I love my 19" VMR710 but damn the roads dwon here in Puerto Rico are killing them (BENT!!)

The OEM sport package uses 225/40R18 tires on 18x8 wheels front and 255/35 on 18x8.5 wheels rear. 225/45R18 fronts would be too tall.

Thank you very much Labalamp425 and cssnms (and all). This is exactly the sort of info I was seeking. Nothing seemed more confusing to me that all the discussions around wheels. There are a great many wheels available used and I'm think of keeping my 17 inch rims for winter driving, as they have a set of PS2 A/S on them and picking up a used set of 287 rims for the summer. I was really hoping that that could just be a swap without doing anything other than balancing.

You should be fine doing a straight swap. My 335i coupe has the sport package with staggered summer tires, but for winter I have a separate set of 17-inch wheels with 225/45R17 tires all around. I do the swap myself and have no issues.

If you want to go up to 19-inch wheels (not sure why you would, but throwing it out there) the OEM sizing is 225/35R19 front and 255/30R19 rear.

Thanks again for the advice Lavalamp.