Camber in solid rear axle cars

[Ron Earp]

How are people getting camber in live axle cars? About the only way I can figure is to bend the rear housing and axle tubes or cut them off and re-weld them. But, this would cause some issues with bearings, sealing, and lifetime, not to mention would be illegal?

R

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Ron Earp
NC Region
Ford Lightning
RF GT40 Replica
White Jensen-Healey ITS
Silver "Skull" 260Z ITS
Email: "rlearp at gt40s.com"

[Speed Raycer]

Dig a hole and get prepared Ron....

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Scott Rhea
It's not what you build...
it's how you build it
http://www.izzyscustomcages.com/images/IzysLgoSm.jpg (http://www.izzyscustomcages.com)
Izzy's Custom Cages (http://www.izzyscustomcages.com)

[Ron Earp]

Hmmmmm.....maybe I should have searched for this first???? And I run a damn forum for god's sake, I should have known better. So I take it this is a "grey" area? Kind of hard to be grey if you've got a solid axle car and I'm looking at it and it clearly has 2 degrees of negative camber, but I suppose it could be bent in an accident or a manufacturing snafu. Or sitting on a hill in poor light. I suppose.

R



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Ron Earp
NC Region
Ford Lightning
RF GT40 Replica
White Jensen-Healey ITS
Silver "Skull" 260Z ITS
Email: "rlearp at gt40s.com"

[dickita15]

If I may recap. one side will say that no factory spec exists for the camber on a live axel car so you can certainly search junkyards for ones that are bent in the manner you would like. while you can not perform an unathorized modification, because there is no spec if you have one that is properly bent, then how can someone say it does not conform.

The other side will say, of course they do not give a spec everone knows it should be zero.

Dick Patullo

[wbp]

Some FWD cars with solid rear axles have rear camber adjustable with tapered shims. Alignment shops will have those shims in stock.

[Ron Earp]

<font face=\"Verdana, Arial\" size=\"2\">so you can certainly search junkyards for ones that are bent in the manner you would like. while you can not perform an unathorized modification, because there is no spec if you have one that is properly bent, then how can someone say it does not conform.</font>

Or find one, say, in my garage where it came to rest after two friends that I didn't see dropped it from 10' onto two 6"x6" wood blocks without the pumpkin being supported, but held level, thus bending the axle tubes up 1/4"?


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Ron Earp
NC Region
Ford Lightning
RF GT40 Replica
White Jensen-Healey ITS
Silver "Skull" 260Z ITS
Email: "rlearp at gt40s.com"

[This message has been edited by rlearp (edited July 26, 2005).]

[Dick Elliott]

In the old Trans-Am days, you could order a houseing from many locations, that had up to 2 deg neg camber per side. Most all used floater rear ends, so the axles had splines on both ends. Then the axles had the splines cut on a radius. By doing this the axles could move around in the center section and at the hubs without binding. The people that tryed this by bending the houseing at home with a press and torch, sometimes would not last a full day without the bearings failing or worse. If you try this on a non-floter rear end, about 1 deg per side is all you can get without problems. It also uses HP because of mis-alignment. All my RX-7s in the 80s had this with no problems.

[This message has been edited by Dick Elliott (edited July 26, 2005).]

[racer-025]

Originally posted by wbp:
Some FWD cars with solid rear axles have rear camber adjustable with tapered shims. Alignment shops will have those shims in stock.

Exactly. These shims are tapered. Used in a pair, you can gain neg. camber as well as toe out/in at the same time. We used them for years on our 3rd gen Civics.

[Knestis]

The most blatant example that I've ever seen of this approach was in the trailer of the Saleen ESCORT endurance Mustangs, back in the late '80s. They had a rack of rear ends with camber adjustments noted on them in white paint pen. And they were NOT all symmetrical, I don't believe...

K

[RacerBill]

Ron: My Shelby Charger has a similar setup. The spindle is mounted to the axle with four bolts that can be shimmed for both camber and toe.

[ddewhurst]

Ron, do a dab of weld on the top side of a axle tube & witch the negative camber grow with the size of the weld dab.

Have Fun http://ITForum.ImprovedTouring.com/wink.gif
David

[Speed Raycer]

Might want to measure Toe before you start "dabbing" so you can keep an eye on if the end moves fore/aft...

------------------
Scott Rhea
It's not what you build...
it's how you build it
http://www.izzyscustomcages.com/images/IzysLgoSm.jpg (http://www.izzyscustomcages.com)
Izzy's Custom Cages (http://www.izzyscustomcages.com)

[Ron Earp]

So, this welding on the tube in the localized top area heats that up, and then on cooling bends the tube up?

R

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Ron Earp
NC Region
Ford Lightning
RF GT40 Replica
White Jensen-Healey ITS
Silver "Skull" 260Z ITS
Email: "rlearp at gt40s.com"

[lateapex911]

How many axles are "found" with "natural" camber....and weld blobs???

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Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]

[ddewhurst]

***and weld blobs???***

Jake, if I knew how to attach a little icon with a file I would. http://ITForum.ImprovedTouring.com/tongue.gif

Have Fun http://ITForum.ImprovedTouring.com/wink.gif
David

[Chuck Davis]

Originally posted by rlearp:
How are people getting camber in live axle cars? About the only way I can figure is to bend the rear housing and axle tubes or cut them off and re-weld them. But, this would cause some issues with bearings, sealing, and lifetime, not to mention would be illegal?

R

[Chuck Davis]

I have done several VW rear axles by cutting a slot behind the stub axle mounting plate, carefully measuring and rewelding. Along the way I found steel shims which I used to make any fine adjustments needed for proper rear wheel alignment. In my opinion there should be no more than 1 and 3/4 degrees negative and very little tow. Striaght is probably best.

[Speed Raycer]

Originally posted by lateapex911:
How many axles are "found" with "natural" camber....and weld blobs???


I don't know about camber, but I know of one that found it's "natural" toe again.

[joeg]

Actually a smidgen of toe-in is good on the rear of an FWD car. Zero is OK too.

I rate bending live solid axles with tweeking the unibody on a frame machine. Do you realize the "official" manufacture's tolerances on dimensions?

Cheers.

[lateapex911]

Originally posted by Chuck Davis:
I have done several VW rear axles by cutting a slot behind the stub axle mounting plate, carefully measuring and rewelding. Along the way I found steel shims which I used to make any fine adjustments needed for proper rear wheel alignment. In my opinion there should be no more than 1 and 3/4 degrees negative and very little tow. Striaght is probably best.



You DO realize that, for SCCA IT at least, the legality of those actions is, shall we say, dubious at best....



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Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]

[evanwebb]

For what it's worth, Mark Donohue in his book "The Unfair Advantage" talks about how they tried this on their TransAm Camaros and never had any success with it and rated it as a big time-wasting failure. But, probably the easiness of doing this depends on the variations in design of the live axle between manufacturers, and besides I'm sure we're all smarter than Mark Donohue anyway ;-) As another aside, the english Mallock cars used live rear axles for many years in preference to IRS and there was an article about 10 - 15 years ago in Race Car Engineering about all their "magic" tricks to make live rear axles work very well for road racing, you might want to find that...

[Dick Elliott]

In the old days, both Mark and Roger, were famous for their reverse psychology. Nobody in the pits beleaved a word they said. He was fast for only one reason. His own driveing. Mark knew how to play mind games like nobody I ever met. He liked to play a game called "The dozens". Very smart person.

[This message has been edited by Dick Elliott (edited August 01, 2005).]

[Allen Brown]

I just pulled the rear end out of the old GSL-SE. Out of the IT car and to transplant into the GT car.

I thought now that I am changing classes I could add some camber. I had been told previously to keep less than 1 degree or one will have binding issues. I have always thought my car was more stable than some of the other 1st gens on the track going through the corners.

After measuring the tubes about a half dozen times...I had 0.75 on the passenger side and 0.8 on the drivers side. And the toe in was as close to 0 as I could measure. I had never tweaked it duringf the five years it was in the IT car....But I have always thought my car was more stable than some of the other 1st gens on the track when going through the corners.

After 15 years on the street and 5 years of being beat across the curbing the diff is as close as one could hope without going to a floater setup. Oh well....sometime being a bit lucky is just fine...

[lbhgti]

Originally posted by rlearp@Jul 28 2005, 01:16 PM
So, this welding on the tube in the localized top area heats that up, and then on cooling bends the tube up?





The material will contract upon cooling more than it will expand upon heating, thus bending the tube slightly. Read more about it in the book "Chassis Engineering"

Pretty neat trick if you ask me. Of course, you&#39;d have to find one of these pre-heated and cooled units in a junkyard.