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Any detailed tech info out there for mounting the BMW 120mm (4.72") bolt pattern wheels to the Chevy 4.75 (120.65mm) hubs.

Thanks
 

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I wouldn't do it unless you can get the wheels machined properly so the lugnut will seat properly. Just elongating the holes will not allow the lug to seat correctly and that could lead to problems.
 

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Or, have new holes drilled for the BMW spacing and go from there.

I had Mosers redrill everything of mine so I could mount my new pony-car "Bullitts"...

AND if I can't find a generic center cap, the pony caps will have ta stay too!!

pdq67
 

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You do not need to do anything to the wheels to bolt them up. Just put them on like regular rims and torque them down. Use a tuner or chrome closed cap lug nut, works fine. I personally know of half a dozen people who run then on daily drivers-1 even went on power tour with them, thats over 2,000 miles. Lots of "wives tales" about them falling off. The difference at each lug nut is only .015".

I like these- Ebay
 

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All the BMW wheels I've seen don't have enough backspacing. Even the ones in Dennis' eBay link. So I assume guys need to run wheel spacers/adaptors to make them work. I've also looked into these but don't like the added cost of the adaptors to make them work.
 

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In the link I provided the fronts which are 8" wide run 5" b/s and the rears which are 9.5" wide run 6" b/s. I would think they would fit.
 

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Originally posted by dennis68:
In the link I provided the fronts which are 8" wide run 5" b/s and the rears which are 9.5" wide run 6" b/s. I would think they would fit.
That's about a 1/2" (maybe a little less) more back spacing than a '69 can handle without some kind of mods. Relocated shocks and mini tubs in the back and removing the inner fender in the front. The '69 actually has the deepest of the 1st gen wheel wells so the same would be needed on the on '67 & 8s. There's the possibility of using a rearend that is wider at the axle flanges that teh factory 1st gen rear and having the rears fit too... Thin wheel spacers are a possibility too with the right stance and a fender lip rolled under.
 

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I guess I need some help on the backspacing measurement. The eBay add says the wheels are 18"x8" with 13mm offset and 18"x9.5" with 25mm offset. Doesn't 13mm = 0.51" and 25mm = 0.98"?

From what I get off this site optimum offsets are front with 8" wheel 4.75" and rear with 9.5" wheel 5.5". Somebody set me straight as I like the idea of the Bimmer wheel due to the cost and style.
 

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I took Denny's back spacing as correct... 13mm is .51" so an 8" wheel with a .51" positive offset would have a 4.51" back spacing.

.98" is correct for the 25mm positive offset and on a 9.5" wide wheel would make the backspacing 5.73".

The 4.75 (8" wide wheel) and 5.5 (9.5" wide wheel) front and back are what I've seen as the largest recomended for front and rear disc converted 1st gens. I know drums in the rear 5.5's work but tend to be a little tight on the inside. I don't think 4.75's would be a good idea with drums up front. Just bringing that up as it shows there are margins of play involved and the bmw wheels might indeed fall within them...
 

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Originally posted by DjD:
I took Denny's back spacing as correct... 13mm is .51" so an 8" wheel with a .51" positive offset would have a 4.51" back spacing.

.98" is correct for the 25mm positive offset and on a 9.5" wide wheel would make the backspacing 5.73".

So If I were using a 70 Camaro rearend which is .5" wider on both sides, I should have no problem with the rears, right? I've bolted the 5.5" bspaced 17x9.5 Centerlines off the front of my Chevelle on the rear of my Camaro with the stock rearend and had .5" clearance on the inner tub. I was going to use TTII's on my car, but I like the looks of the Bimmer wheels. Do you think a corvette center cap would fit in place of the BMW insignia? And as far as the 5 on 120mm bolt circle actually being 5 on 4.72, and gm is 5 on 4.75, there is a difference of .030". If the size is off by .015 per hole on two holes spaced across from each other when you initially tighten in the 5 star sequence, and your using tapered lug nuts, would the first nut in the sequence not pull the wheel on center to it, causing a .03 off center wheel? Would this cause vibrations at high speeds?
 

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As stated earlier, no problems on the several cars I know of running them. Although the wheel would not hubcentric it would still be centered on the studs which should be darn close.

Would runnig all 4 18X8's make the fit any easier? It would allow for 4 tire rotation and an 8" wheel is still enough to squeeze a 265/35 onto, although I don't know if a 265 would fit on the fronts.
If the size is off by .015 per hole on two holes spaced across from each other when you initially tighten in the 5 star sequence, and your using tapered lug nuts, would the first nut in the sequence not pull the wheel on center to it, causing a .03 off center wheel? Would this cause vibrations at high speeds?
The lugs should always be drawn down evenly, you should not have any 1 lug torqued before all the others are at least snug. I always bring mine down in steps; snug, 25, 45, 65, 95, 105. Can't be too careful with Al wheels.
 
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