Club Cobra - Urgent Jaguar IRS / pinion angle question

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Urgent Jaguar IRS / pinion angle question

I have a friend from out of town over helping install my drivetrain, and he's only available for a limited time. We're having problems getting the driveline angles set in my Contemporary. We can make any adjustment we want in the transmission angle, but the Jaguar center section is bolted to a solid top mount. Right now the pinion angle is 5 degrees facing up. How do I lower that angle? Ideally I'd like 2 to 3 degrees. I would have to have the transmission angled down at 5 degrees to make it work properly if I understand everyone correctly in my searches on the subject. I guess I have two questions:

1- Is 5 degrees up pinion angle too much? What would the transmission angle have to be to make this work?

2- If 5 degrees pinion angle up is too much, how do I change it? Again, it's a solid mounted Jag center section, mounted with the top four mounting bolts to a rigid mounting pad welded to the frame.

Any ideas are greatly appreciated. Thanks.

First I would double check your frame to make sure it is level? Are you measuring the angle of the diff to true level or the frame. You need to be consistant on this.
You could also shim the diff in the frame to bring it back down.

The pinion angle (U-jount angle) at the third member should balance out the U-joint angle at the transmission to prevent driveshaft whipping and prevent U-joint brinnelling.

I would just drop the trans to get it as close of an angle to the pinion angle as possible.

To shim out 5 deg. you need a thickness of 5d/57.3,where d is the bolt spacing fwd. to aft. If d is 6 in. the shim would be around 1/2 in. !! Seems like something's very wrong here.

No more than + or - 2 degrees

767 Jockey Doug you have to add shims under the transmission mount to get the number closer to 0. I run +2 on the trans and -2 on the rearend of the car. The camber and toe specs I would have to look up and find. You want the rear - so when you accell the nose comes up a little. The car bites a little more without ripping up the drivetrain. This also stops some of the rearends from hopping. You can get the shims at a speed shop or make then from flat steel from homedepot or Lowes. 3/16 should put you about perfect. Small piece of flat stock and drill 2 holes. The other thing was Mcleod sell a slick shifter for TKO 500/600 trans. It also has the shifter mount from center to 3" off. This might help with the shifter and the boot problem. There are stops on this shifter, Tremec said they void the warranty. I don't see why unless it stop the gear syncro from complete engagment. You can trim the stops to get full engagment without over extending the syncro collars in the trans. This shifter also has shorter throws. Have a good one Rick L.