The angles are relative to one another. If your driveshaft angle is 2.5° down front-to-rear then having the pinion level to the ground means the pinion is 2.5° nose-down already relative to the driveshaft. Having the pinion 3° down relative to the ground would make it 5.5° down relative to the driveshaft. My old Direct Connection Chassis book explains and illustrates this.

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Joshua

Ok, Now I think I got it. Why didn't I think to look in the direct connection manual. I'm pretty sure I have it too!

Rick

Ok, I have the old perches cut off and new transmission mount in place. Here is where I have it bolted down.

Driveshaft 3 degrees down
Pinion 4 degrees down

This makes 7 degrees down relative to the driveline? Is this where I want to be? Looks like it to me according to Josh's formula.

And according to Slantzilla's post I am at 3 degrees down relative to the engine transmission. 4 for the pinion, and the engine/tranny is down 1 degree. 4-1=3 If my math is correct. This too looks correct?

Thanks for verifying this for me before I fire up the welder in the morning.

Thanks, Rick

Is that with the suspension at normal ride height/loaded?

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Joshua

Yes it is. It is up on stands but with the suspension loaded.

Rick

Are you using a pinion angle tool or a protractor to measure? Very easy to adjust with a magnetic degree tool. What Am I saying? Of course you do. If not Craftsman makes a good one. the magnet holds it on while I hammer and say words. I agree with Josh 5 t0 7 pinion down for racing. For a stocker 3 t0 5.
MaX

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1966 barracuda 360
1964 signet conv. 170 turbo
Bonneville or Bust 2012

Yes I bought the "premium" magnetic protractor from Sears.(Still only about $10) Ok then I have everything bolted down tight and I am still where I was. So Out comes the welder! Thanks to everyone for the help.

Vibration be gone!!! Shazammm!!!

Rick

PS. I did find in the Stockel automotive repair manual that the maximum runout in the center of the driveshaft should not exceed .030. And I am right at .030, so we will just have to see. Probably will end up with a new shaft shortly anyway.

I believe the vibration is 80% gone. I will have to let Ryan drive it and he can tell me what he thinks. Upon further inspection the rear u-joint is a little loose. Since this is the damaged area around the caps I don't think they will press out. With the drive shaft obviously on the edge for run-out anyway, I think it is time for a new shaft. Hopefully another shaft will get rid of the little vibration that is left.

Thanks to all,

Rick

Great work, Rick! Thanks for the complete descriptions too. Ryan is a lucky guy...

Lou

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