8 1/2 Front Wheel Fitment (FWIW)

[M3inSC]

In the "for what it's worth department", many people have asked about the fitment for larger front wheels ...

I have 8 1/2" M Double Spoke II wheels on the front of my 98 with stock springs and Koni SA cartridges in the stock strut housings with no camber adjustments, i.e. camber plates, etc. The stock offset of these OEM wheels is 41mm. They have Michelin MXX3 245/40's on them.

These wheels required spacers to avoid rubbing the front strut housing.

I had H&R 15mm front wheel spacers, but they were lost (stolen!)... long story. But the wheels were actually a little too wide, i.e. the tires were slightly outside the front fenders! I have 80mm studs from TC Kline. These "permenantly" screw into the hub. The nice black aluminum acorn nuts from TC Kline fit fine with the long studs and the 15mm spacers.

Anyway, I replaced the spacers with 5mm spacers to save a little replacement cost. The wheels clear the struts just fine with this smaller spacer and the wheels fit better in the fender wells. But the studs are too long. I have to use the steel open end lug nuts from TC Kline and the studs stick out about an inch past the nuts. The front looks like a Roman chariot! The proper setup with the 5mm spacer would be to use the standard size 58mm studs and then, I think the nicer acorn nuts would fit then.

Also, if you are shopping for larger front wheels or want to have the same size wheels all around, an 8 1/2" wheel with an offset of 36mm or less would fit the front without a spacer. Please note that this size wheel would push the rears out a little and there is not much room there without fender rolling. Using spacers in front alleviate any problem with fitment in the rear and you can rotate your tires on all four corners.

Of course if you have different front struts/springs or more camber in the front, your results may not be the same! This is with stock springs, stock front strut housings, and stock camber.

Also, I have been told by many people that the 8 1/2" BMW OEM wheels would not fit in the spare tire compartment in the trunk. I found an 8 1/2" Contour and it fits fine if you slide the wheel just a little to the rear when you tighten down the wing nut and washer. No problemmo!

[nodemgr]

Thanks for the info! I had been wondering about this. Now I wish I could find 2 8.5" doublespoke II's forsale, but it looks like I will have to buy a whole set. Although then I could use the 7.5" for winter.

[Mode]

Thanks for the info M3inSC! I know many, including myself, were interested.

[Jim Bassett]

Originally posted by M3inSC

I have 8 1/2" M Double Spoke II wheels on the front of my 98 with stock springs and Koni SA cartridges in the stock strut housings with no camber adjustments, i.e. camber plates, etc. The stock offset of these OEM wheels is 41mm. They have Michelin MXX3 245/40's on them.

These wheels required spacers to avoid rubbing the front strut housing.

[snip]

This is with stock springs, stock front strut housings, and stock camber.

Odd, because I and many other people have run the 8.5" wheels up front with stock suspension with no spacers, and no rubbing whatsoever.

My current setup is stock Contours (8.5", 41mm offset) with 245/40/17 SO-3s. I've also run Pilot Sports and Yokohama AVS Sports, again with no rubbing and no spacers.

The wheels will fit, no problem. The issue is the tires. I've heard that the BFG KD, for example, will rub because it's very square and tends to run a bit wide.

If you're running the stock staggered setup, and are thinking of going with 8.5 up front, the easy test is to put the rears on the front and the fronts on the rear. You can go for a short test drive [be careful: oversteer ], and even mark the strut tube with shoe polish or chalk.

My 2 cents,
Jim Bassett
1998 M3/4 - no spacers
1993 325is #44 KP - spacers due to big brakes up front

[UD///M]

I put my 8.5" Coutour wheels on the front of my car once just to see if they fit. No rubbing occured. There was about enough space between the inside of the tire and the strut to get the tip of my finger between. I tried flogging the car on some corners but never heard a rub.

This was with no spacers and with bilstein sport monotubes and stock springs.

[badmonkey]

I also have oem 8.5" rims on the front with 235/40-17 V700 Ecstas. Clears my H&R coilovers, but very close. A 5mm spacer gives plenty of clearance from the spring/perch. With 255/40's I've used a 15mm spacer, gives lots of clearance from spring, but will also require about -3.5 camber to clear the fender. A 10mm spacer would be ideal with 255's on oem 8.5's. YMMV.

///badmonkey

[Gatorbait]

Good write-up M3 in SC. A question, though (for anybody): are there any disadvantages to using spacers? Are there problems with wheel balance and/or handling problems with the wheels that are affected?

[Jim O.]

Originally posted by Gatorbait
[BA question, though (for anybody): are there any disadvantages to using spacers? Are there problems with wheel balance and/or handling problems with the wheels that are affected? [/B]

Well, since you asked for the disadvantages, here are the ones I can think of, or have run across:

Potentially, spacers can put more stress on your wheel bearings, making them wear out earlier. This happens with the wider spacers - the narrow ones shouldn't be a problem.

Depending on how wide of a spacer you use, you can screw up the scrub radius of the front wheels, which will make the steering a lot heavier, and make the car slower to react to steering input.

They also increase track width, so if you use them on the front, you'll have less understeer, which is a good thing for higher-performance drivers, but might be a little less desirable for a poorer driver.

Depending on the thickness of the spacer and the machining of the centerbore of your wheels, you can possibly have imbalance problems. The thinner spacers (less than 10mm) can't extend the hub any, so the wheel has to sit on whatever portion of the hub is left sticking out. Sometimes this is too little to really center the wheel. Especially if the centerbore has a little chamfer on the outside edge. If that happens, probably the thing to do is go to a 10mm or 15mm spacer - the H&R ones have their own hub for the wheel to sit on, so you don't run into this problem.

Jim

[M3inSC]

Originally posted by Jim O.
Depending on how wide of a spacer you use, you can screw up the scrub radius of the front wheels, which will make the steering a lot heavier, and make the car slower to react to steering input.

Jim

You've got me on that one. What the heck is "scrub radius"?

One other thought. If you are going with wider wheels in front, it is probably because you are doing some performance driving or want to improve your tire wear by being able to rotate your tires from front to rear.

In any case, if you do not use at least a 5mm spacer in front, the clearance between the wheel/tire and the strut is so small that you increase the possiblity that you could get some road trash or whatever wedged up between the gap and that would not be good. I think its a safer bet to just get the 5mm spacers and be safe. There are really no disadvantages to a small spacer.

And Jim is right, the rib on you tire, if it has one, can be the difference between a wheel/tire combination fitting or rubbing against the strut housing.

[Jim O.]

Originally posted by M3inSC
You've got me on that one. What the heck is "scrub radius"?

Project a line down through the axis that the front wheels turn around when you turn the steering wheel, to the ground. The distance between the center of the contact patch and that line is the scrub radius. Ideally, when you turn the steering wheel, the tire will just spin on the ground - that makes the easiest, quickest steering. If you add spacers, and depending on the offset of the wheel, the contact patch will make an arc around the pivot point, making the steering heavier.

In any case, if you do not use at least a 5mm spacer in front, the clearance between the wheel/tire and the strut is so small that you increase the possiblity that you could get some road trash or whatever wedged up between the gap and that would not be good.

I've been running 17x8.5 wheels with 245/40-17's all the way around on my car for the last 5 years, without any spacers. Never had any road trash wedged in between the strut and the tire.

Jim