Pinion Angle Help

[roccodart440]

I am using RMs boxes. I plan to use the upper rear hole so the front eye will be raised up 1.5" to lower ride height.

I am ordering a new Dana 60 from Dr. Diff. He wants to know what spring seat angle I want. I could go stock and rely on shims to fine tune or I could take some out. I.e. 5 degrees is stock, 3 degrees would be the new settting etc.

 

[bOb shingler]

I am using RMs boxes. I plan to use the upper rear hole so the front eye will be raised up 1.5" to lower ride height.

I am ordering a new Dana 60 from Dr. Diff. He wants to know what spring seat angle I want. I could go stock and rely on shims to fine tune or I could take some out. I.e. 5 degrees is stock, 3 degrees would be the new settting etc.

measure the stock rear first and see what that is or is that what you did to get the 5 degree reading. if you're using leaf springs I believe 3 degree won't be correct. what type rear suspension do you have?

 

[69MOPE]

I would have him send the perches not welded on. The angles you are changing may make it that you might need a shim larger than is safe or available. Bolt the rear in, mock up everything, that means engine and trans in and full curb weight then tack the perches, pull the rear, have them welded on.

 

[roccodart440]

measure the stock rear first and see what that is or is that what you did to get the 5 degree reading. if you're using leaf springs I believe 3 degree won't be correct. what type rear suspension do you have?

To: Farina, James
Subject: Re: Dana 60 Order


Stock A-body pinion to perch angle is 5 degrees up. If you raise the front spring eye hole 1.5", while leaving the rear spring eye at the stock height, I estimate a 3 degree pinion to perch angle will compensate.


Cass

I would have him send the perches not welded on. The angles you are changing may make it that you might need a shim larger than is safe or available. Bolt the rear in, mock up everything, that means engine and trans in and full curb weight then tack the perches, pull the rear, have them welded on.

I am geting it powdercoated so they need to be welded on before coating.

Considering they make 4" spacers for springs i'm sure shims can correct it. The billet shims Dr. Diff caries are 3 degrees and are safe.


I can weld, that sin't the problem.

 

[383Scampman]

Tapered shims are perfectly acceptable and are available at any spring shop for cheap. My chassis guy says to weld the perches 90 degrees to the pinion centerline and shim from there. Do not shim unless car is at ride height. Hope this helps

 

[qkcuda]

I'm running a stock rear with shims to set the pinion angle, no problems at all. I would go with his recommendation and fine tune from there.

 

[DTMRacing]

I'm on board with the 3* as well. You can buy shims from .5* to 3* to get it really dialed in.

 

[bOb shingler]

To: Farina, James
Subject: Re: Dana 60 Order


Stock A-body pinion to perch angle is 5 degrees up. If you raise the front spring eye hole 1.5", while leaving the rear spring eye at the stock height, I estimate a 3 degree pinion to perch angle will compensate.


Cass









I am geting it powdercoated so they need to be welded on before coating.

Considering they make 4" spacers for springs i'm sure shims can correct it. The billet shims Dr. Diff caries are 3 degrees and are safe.


I can weld, that sin't the problem.

ok, I see what you mean, go for it

 

[67Dart273]

And IF you use shims make SURE they are STEEL and not "pot metal" or "alloy."

I'll be dammed if I know why "they" even MAKE non-steel shims. Even (truck) front axles take a lot of pounding.