ASK ALL WHEEL/TIRE FITMENT QUESTIONS HERE - The Official Wheel/Tire Fitment Thread

[Mystikal]

First off sorry everyone for being MIA for a week. Had my graduation and stuff, partied for 7 days straight. :p

hey jay, how will the fitment be on a 89 325is with bilstein/h&r sports with 15x7 et 20 with 205/50/15 azenies?

No problem at all. No fender rolling.

[Mystikal]

17x8 - +35 offset
17x9 - +35 offset

What size spacers will i need? I have 20mm ones are available.

cheers again :)

Oh and what do you think these look like? Im liking them

20mm is a lot for them. But that will fit fine with stretched tires, like 205/40/17 front and rear. With the 20mm and 205 tires, you'll still need to roll the rear lips just a bit (I think you already did this for your current wheels, no?).

[Mystikal]

Have a quick question...will kopi 17's fit under 60/30? Thanks Jay. I know youve probably answered this one quite a few times but I didnt feel like looking through a few thousand posts. ;)
Ian

ps this was post 600! haha. damn im a post master now.

They will, with up to 215/40/17 tires. You may have to roll the rear lips slightly, depending on how low the rear gets (a 30 drop isn't that drastic).

[Mystikal]

Just got a set of 20mm CNC aluminum spacers in 4x100/5x100, 57.1mm hubcentric for $118 shipped! Real nice pieces - let's be honest though, they're hunks of aluminum, there isn't much to them, so it's not like I NEEDED a brand name.

Tires - now that the wheels, spacers and suspension are set, you tell me - the car doesn't see rain, and I plan on running a few autox's and ADSS's and trashing the tires, so I don't want anything expensive, in fact the cheaper the better. I have two 205/45/16 Pirellis that are in great shape - a bit undersized but whatever. I may grab another two tires in that size and burn through them, but if I decide to get four - what's the best size to run? One more time:

16x7ET40, 20mm spacers, H&R race/Bilstein Sports on e30 vert

PS: from BMP's website:
All BMW factory wheel bolts are 12mm diameter with a 32mm length...For spacers 15 to 20mm use 50mm studs.
Even if their opinion of what sizes to use is just that - an opinion - I'm using simple monkey math:
32mm (stock lug bolt length) + 20mm (size of spacer) = 52mm < 60mm (size of stud kit that I purchased :) )

Good info. I thought I remember reading a while back that stock lugs are ~35mm, so the spacer vendor site I read before posting that claimed you needed 80mm for 20mm spacers seemed off. But I still listened, which was a stupid move. Thanks for the clarification.

As for your tires, 225/45/16 is a perfectly suitable size. For your wants look into the Hankook R-S2 in that size, and the Falken RT-615 in 215/45/16. Both love hard driving, and are pretty cheap.

[Mystikal]

I'm sure this has been answered in this thread, but i've gone through 25 pages of it without finding it straight out answered...

I'm planning on buying some borbet type A's 16x9 et15. From what i've gathered, i'm going to need a small 3-5mm spacer up front to clear the strut, but other then that and fender rolling they will fit fine right? Out of curiosity how much fender rolling will I have to do? As well, will i be able to mount a 225/45 tire without any problems?

Sorry, I answered your PM. 5mm spacer, 215/45/16 max without serious fender work. 215/40/16 is easier to fit and more tires available.

[Mystikal]

1) Why does having a 17+ in wheel allow for more rubber to fit under the car? I dont understand why a 15 incher cant go past 225 in rubber (w/out fender modification) when a larger wheel (17 inches plus) can go 245 with fender rolling. I wanted a 15" wheel at most because I like the RPM of smaller wheels but I might want to go with 235's so that means I have to go with 17x8 or 17x8.5 right?

Adding to what my protegé over there stated (and nicely so), the other issue with 15's is that there aren't many tire options in E30-friendly diameters past 225 in a 15". The new Toyo R-comp is a 235/50/15, and that's about it.

[Mystikal]

Excellent info Maniac (sorry for calling you that), I am going to check on those wheels but with the accurate info you are telling me, I think it will probably be a better option for me to go with 15s, do a slight fender roll and go with the 225s.

What can you recommend me as far as a pretty light 15x7.5 or 15x8 wheel?

What sidewall percentage would be good for a 225 15"? - I should go with Azenis or RS-2s if I want to follow Jay's advice right?

I like the kind of look Ed has, but that may be due to his deep lip and small space b/w his front tire and the fender. Very sexy.

Thanks again Jay and Maniac.

The 18racing.com exclusive 15x8 Rota Slipstream is a great option. It was custom-made for our cars, with 57.1mm hub and ET20 offset. It weighs like 15-16lbs. This is a good match with 225/50/15 R-S2s, but get the fender roller ready; it's a very aggressive fitment.

[graphikg]

I am loving the info man. Thanks a lot. Scaffolding me like crazy. 1 mo quick question though if thats alright. Can I go with 225/45/15s ? or 225/40s ? Or would that be too rough of a ride?

What about this as an e30 option for 15x8? http://949racing.com/index.asp?PageA...&ProdID=2&HS=1

[ZinnoE30]

How do you feel about staggered tires on the same size wheels f&r? 16x8 with 225/45's and 245/45's. Good idea? Bad idea?

[Mystikal]

I am loving the info man. Thanks a lot. Scaffolding me like crazy. 1 mo quick question though if thats alright. Can I go with 225/45/15s ? or 225/40s ? Or would that be too rough of a ride?

What about this as an e30 option for 15x8? http://949racing.com/index.asp?PageA...&ProdID=2&HS=1

Yep, a 225/45/15 will fit, and will actually require less fender work. Especially for the R-S2, the 225/50/15 is A LOT wider than the 225/45/15. Add that to the shorter overall height and the 225 is significantly easier to get under there.

As for those wheels, they look pretty good. Keep in mind you'd need a 20mm spacer (or 15mm with the ET36 version I see they make).

[Mystikal]

How do you feel about staggered tires on the same size wheels f&r? 16x8 with 225/45's and 245/45's. Good idea? Bad idea?

Honestly nothing to worry about. There will be a slightly different feel at the limit (the rear sidewalls will be more flimsy than the fronts), but at anything under 10/10ths you won't notice.

[E30SPDFRK]

Hey Jay, I'm thinking of getting these wheels-
16x8 front et32
16x9 rear et27
5x130

My question is, what size adaptor would make these fit best? I would prefer flush with the fenders (mine are slightly flared), but I am not opposed to a little poke. I think H&R only makes 20mm and 25mm 4x100-5x130 adaptors.

[ethirdy]

Good info. I thought I remember reading a while back that stock lugs are ~35mm, so the spacer vendor site I read before posting that claimed you needed 80mm for 20mm spacers seemed off. But I still listened, which was a stupid move. Thanks for the clarification.

As for your tires, 225/45/16 is a perfectly suitable size. For your wants look into the Hankook R-S2 in that size, and the Falken RT-615 in 215/45/16. Both love hard driving, and are pretty cheap.

Awesome - I really appreciate you taking all this time and answering everyone - glad to see you took some time to yourself!

I'll be putting them on the fronts tomorrow using the Pirellis I have in 205/45, then grabbing a set of RS2's on Monday most likely. Should I grab them in 205/50 (the best size for the car) or 205/45 (to match the fronts)? I don't think it'd really matter if I ran 205/45 in the front and 205/50 in the rear, right?

[graphikg]

Yep, a 225/45/15 will fit, and will actually require less fender work. Especially for the R-S2, the 225/50/15 is A LOT wider than the 225/45/15. Add that to the shorter overall height and the 225 is significantly easier to get under there.

As for those wheels, they look pretty good. Keep in mind you'd need a 20mm spacer (or 15mm with the ET36 version I see they make).

What do you mean by this? Are you saying that the 225/50 is a lot wider in the sidewall than the 225/45? Or are you talking about the contact patch being wider. I would think all 225s would be the same width no matter the sidewall size.

One quick question though. would a 225 fit on a 15x7.5 or 15x7? Thanks again guru.

[z31maniac]

^Yes two tires that are listed as the same size can be very different once mounted, even on the same width rim.

Tire manufacturers are responsible for sizing their tires, so there is no real standard that they have to meet.