MGB: Saab wheels ala MG, continued

Thought I should start a new topic so those that are interested would be sure to see it. This is what I know about the Saab 90/900 wheels:

BTW, I thought the center caps looked GREAT!!!! I have been wondering what to do to keep the MG theme on my wheels.

My measured offset of the Saab wheel is 46 mm positive. My calculations are based on the MGB Rostyle having a 28 mm positive offset.

According to Glen Towery (based on my faulty memory), he runs a 3/8" aluminum wheel spacer for the Saab wheels. This is what we discussed when he was here picking up a Buick 300, and I showed him my Saab wheels.

My calculations show that 3/8 is too little and 1/2 is too much. To get the exact outside rim location of the Saab wheel to the same as the stock MG you will need a spacer of 0.472441 Inches. This will still place the INSIDE rim edge 12 mm closer to the inside wheel well. However, since the Saab wheel is 15" instead of 14" there is no trouble of fouling tie rod ends or front suspension. Sorry, I haven't checked the rear yet. Also, my checking was with bare rims (no tires).

That being said, I think I would go with 1/2 inch spacers since that will place the outside rim only 0.6999 mm farther out than stock.

Now I just wish someone would make up these spacers for those of us that need them!! Saab wheels are plentiful and cheap.

Here are some of the online references that I use for this type of calculation:

http://gs.tolan-hoechst.com/tirecalc.htm

http://www.mercurycapri.com/technical/suspen/woc.html

http://www.c5-corvette.com/tirecalc.htm

http://www.dakota-truck.net/TIRECALC/tirecalc.html

http://www.seansa4page.com/resource/autotech.html

Michael...sounds lie a tech tip for my site...wanna write it up? oh, send me the measurements & I'll se what my machine shop can do...depends on diameter of stock......they ARE good looking wheels!

Sure! I will take some pics. It is storming here today in western Arkansas, so I will get to work on it. What file format do you want it in?

Mike

Whoaaa.... Hold on a minute there... Are you saying the B will take up to 46mm of offset with a spacer? If so, to heck with Saab wheels... the world's our oyster. How bout ALL VW wheels, 4-lug Toyota, Mazda, Nissan, Acura, Honda.... oh heck... all of 'em. 46 is a lot of offset. Most cars these days run around 40, give or take a few. I've seen some Acura wheels that were pretty close to the old University Motors Special alloys from the 60s... look good on a B.
Cheap spacers can be had from JC Whitney. For good ones, go to BMW parts places. 2002/320 guys use 'em quite a bit. Pricey, but top quality.

You are right Baxter.

The tech data says that the Saab wheel has +40 mm offset. However, I used the method described here: http://www.corrado-club.com/corrado/faq/offset.html and came up with +46 mm offset. I will re-measure as accurately as I can and, if neccessary, use the correct offset to write up the spacer required for Tony's site.

Here is the list (thanks to Dave Williams, http://www.angelfire.com/ar/dw42/, [a good source for engine weight info, also]). You will have to find the correct offset since they are not listed.

BTW, Dave is an excellent engine builder!!!


4 on 4-1/2 (114.3 mm)
Acura - Legend '86-'89
Buick - Special '61-'63
Chevrolet
Corvair all 4-bolt
Chevy II all 4-bolt
Sprint '85-'87
Nova ('61-'70)
Datsun/Nissan - most models to '89
Dodge Colt '79-'88
Dodge Colt (early)
Ford
Mustang all '65-'68 4-bolt
Falcon, Maverick, Granada all 4-bolt
Mazda - 626, RX7 '83-'87 ????
MGA, MGB, MGC
Olds - F-85 '61-'63
Plymouth - Arrow, Sapporo '79-'88
SAAB all ???
SAAB - 900 to '87
Toyota - most exc. MR2 and P.U. to '89
Triumph TR 1..6

Well, I see one error in the list -- MGCs are 5-lug, not 4.....

It's nowhere near complete, either. I know BMW used the same bolt pattern, as well as Acura Integras. Probably a gazillion more.
What I want to get at is how much offset can you run (with a spacer), and what problems could the spacer introduce. Are MGBs hub-centric or lug-centric?

I will try to address that in the article for Tony (which I will also post on my website). In the meantime try here and have fun pluggin in the different wheel aspects.

photos in 'jpg format...just send the article as body of email or make it a word document....never thought about spacers! hmmmm

I'd be scared of them. Seems like that would concentrate the bulk of the force further out on the stud adding leverage to the load. The further out you go, the greater the likelyhood of breakage. If you are allready pushing the design with increased HP that increases the likelyhood of breakage even more. I had a 240Z hears ago that the PO had installed wide wheels with way too much offset. I could not keep wheel bearings in the front because of the extra stress. Made it damned hard to drive up a small curb into my driveway without the wheel trying to spin out of my hands. Hit a pothole once and I thought I had broken my wrist! Just some random thoughts

I don't know Gerry!! If you are pulling them tight, where are you loading them?? I do not have a lot of experience in this sort of thing, nor does it really interst me, but I do not think you are putting the load on the outside of the spacer!! If you were, then I doubt that a 4 ply truss would really hold a lot of shear!! We use four ply trusses al the time to hold floor loads!! I know it is different, but I think the same principle applies!!

I've been thinking about it, and I think the key would be to keep the centerline of the wheel in place... luckily, a B pretty much forces you to do this, as you have so little space on either side.I would be concerned about rotating mass, and adding weight to the far ends of the axles, but overall I think it should be OK.

Many racers use them to get that last little (sometimes not so little) bit of track width on their cars. The only car I ever broke studs on was with regular lug nuts and .5 inch spacers. The safest way to use spacers is to use them with mag nuts that reach to a sixteenth or less of the hub. That way the shaft of the stud is supported through the wheel and the spacer. At the moment I have 205/60-13 tires on 7X13 Aluminum wheels on the Pinto with quarter inch spacers on the front wheels and one inch spacers on the back. I torque the mag nuts to 75 lbs.