Looking for shop to do 10 bolt cambered work

[JMarsa]

I'm in the Detroit area, and I'm looking for a shop to set up a 8.5" 10 bolt rear with ~1 degree of camber for autocross.

I'd go with a 9" (lots of circle track shops camber those) if a Torsen T2-R was available for it (although a true-trac is). I'm building a autox/track day car and I'm looking to keep things as light as possible. In my mind a 9" is my second choice since it will cost me more to set up while being heavier and yield less rwhp.

BTW, speaking of circle track/stock car rear-ends. Anyone know if the hub assemblies and axle snouts (wide 5, winters ect.) are durable on the street? We're talking 2-3K mile per year.

Any ideas?

--Jason

[dennis68]

Any "good" alignment shop should be able to accommodate you. Simply concentrating heat to the housing and allowing it cool will provide the camber you seek.

[David Pozzi]

Herb Adams book says .5 deg is max for street use, by street use, I guess he means for it to last without tearing up bearings. I don't know how long the bearings can take 1 deg neg. any of the circle track stuff should handle street use better than stock.

[Mean 69]

Just make certain that you drain all of the fluid out, and clean the thing before they torch it. A ~6" section, heated cherry red in a psuedo-oval shape will yield about a quarter to half degree.

Keep in mind that a degree is pretty much on the hairy edge of what your axles and bearings are going to like. The correct way to do more than this is to use a floating hub, that is cambered and centered on the axle tube via a special snout, in conjunction with a crowned axle. Circle track dudes do this all the time.

As for durability of a floating type hub on the street, I'd say that they will be far more durable and have longer life than the traditional roller type bearings. By far. And you are right, the 9", while really tough, is very heavy. If you are going to do a custom unit, you can use thin wall tubing (even chro-mo) to lighten things up, and use an aluminum carrier too. Not cheap, but it will work really nicely. I think Currie offers a center section case (not the gear carrier) in chro-mo that is lighter than their traditional units. In order to prevent toe out under hard acceleration (which you do NOT want), you can reinforce the rear with some stiffening "ribs," like some of the really beefy drag race cases use.

While you are at it, you might consider a small amount of toe-in when you camber things.

Mark

[BRIAN]

Is this a common practice? I have never heard of anybody doing this to a rear? If used on the street it would have to have it's toll on the bearings. I would also assume it would have to be done empty. I am sure all rears flex to some degree especially stock non welded but if permenantly bent how could it not cause bearing wear?? Not challenging anybody but more questioning how it could be done on a car that is street driven not race car only? I know his post was race car but just curious? Is there real benefit as axle is in motion on most roads or courses anyway?

[dennis68]

It is common on the autox and road course circuit. Obviously IRS has eliminated it to some degree. I used to do a couple of them a week "back in the good old days", more for correcting rear camber and toe to 0 than for introducing negative camber.

Small amounts won't have much affect on bearing wear, 1/2 degree or so is no problem. Running a full degree or more will cause some axle concerns if driven on the street over time. I would guess somebody going to the trouble to set a stick axle up for a degree of neg camber is looking to build a dedicated autox car.

Yes, there are some advantages to setting the rear up with some neg camber. Although the stick axle is not subjected to the same geometry challenges the front is it does still roll to an extent and running neg camber will ensure the tire maintains a full contact patch throughout the turn.

[JMarsa]

Thanks for all the replies. I never thought of an alignment shop. I've been poking around looking for shops like Reider Racing or Moser ect.

David, Funny you mention Herb Adams book. I'm trying to contact Matt Adams (his son) how runs a shop called VSE in Carmel CA. I found some postings online where he had done this work to 10 bolts.

Mark, On the note of weight. There was an article in the Dec. issue of Street Rodder called "Nine Lite" where they listed the weights of axles tubes, center housings, gear housings, gears, pinion supports, yoks, and diffs showing how you can mix and match to lose 30 pounds or more.

I'm hoping to keep it all GM, but if I need to go 9", I'm willing to consider it.

--Jason