Correcting pinion and driveline angles by lowering transmission mount

[beanhead]

Found the issue, stupid me I was measuring the transmission angle using the pan.. turns out the pan and valve body are not parallel to output shaft.. by 6 degrees. The actual angle, measured at the rear pad, was nose up by 1 degree. With the rake of the car, that is exactly what is normal. With this revelation, my driveline angles are all correct. 2 degrees of wrap-up brings me to parallel.

To address the earlier naysay asking why I have Caltracs on a street car (Why do any of us have any of the power or performance adders we have on street cars) consider this. I can stomp on the gas from a standstill and accelerate under full power, perfectly straight, with my hands off the steering wheel. The #3700 car has a mild 360, 3.23 sure grip with 28" tall tires and does a 6.2 second 0-60 (no launch, just mashing gas in D) consistently, every time. Just hooks, and goes straight. High speed turns, such as freeway on-ramps, are rock solid with minimal body roll. This is 100% due to to the suspension setup. You don't have to drag race to appreciate improved handling.

Good, that's an easy fix!

 

[oldkimmer]

If your tranny is -1 and your pinion is -1 that is your problem. U need the pinion to be 3 degrees less so it should be -4. Or raise the tranny up a bit at the mount. Do u have the factory little flat plate between the tranny and the mount?

 

[Darter6]

I went thru this looking for drive line vibrations that drove me nuts. Found out it was a rear axle bearing that was bad.
Just a thought.

 

[Smokinnjokin]

Good thinking, I did just do the rear axle bearings. After a long drive and experimenting, it looks like the vibe is the same whether coasting in neutral or full power... I know the driveshaft is still spinning either way but now I am thinking about possible tire imbalance.

 

[Black_Sheep]

You should probably be more concerned about the pinion angle with the altered driveline position, not the angle of the factory perches. With the tail of the trans hanging lower than stock, you basically need to start from scratch.

 

[oldkimmer]

How and where did u get your pinion angle? 2 degrees May not be enough for your car. Kim

 

[bigbluedodge]

I'm pretty sure I measured my angle from the harmonic balancer face (crank parallel to input/output shaft) Glad you figured it out.

That's what I do.