Pinion Angle/ Snubber Question

[heinz13]

That driveshaft yoke looks like it could go in a little further. Maybe an inch longer driveshaft. Also those springs look kinda flat.

 

[68suprB]

3 or 4, not .75

Time to resurrect this thread…Supershafts, I put a 3º shim in the rear, it changed the vibration rpm window from 2800-3400 rpm to 2400-2600 rpm…so it comes in earlier and goes out earlier..does this make any sense at all? Smooth as glass before and after as before.

 

[krowbar]

Have you ever checked your rear diff. fluid level.

 

[miller]

You also mentioned vertical movement, at the trans tailshaft housing. Bushing could have excessive wear.

 

[68suprB]

Fluid level is good, I had the transmission rebuilt so everything is good there, runout was checked on the input shaft and that was ok too.

 

[nitrojunkie]

I have a diagram around here somewhere but If you draw a straight line lengthwise thru the tranny and output shaft toward the pinion; then draw a straight line thru the pinion toward the tranny those lines should be parallel. (I usually set an angle finder on the tranny yoke and the nose of the center chunk). If the tranny has , for example, a 3 degree downward tilt then the pinion should have a 3 dregree upward tilt (from horizontal). That cancels each other out. If you have one at 3 degree downward and the other is say 5 dregree up (or down) then you will probably have a vibration. I also noticed also that the tranny doesnt look centered on the crossmember. Maybe the mount or mount bolts are broke? The only other thing is have your tires and rims checked on a spin balancer to see if rim is bent or the tire is out of round. I have had that happen to me. Other than that check for tranny bearing or pinion bearing excessive play. Race cars may have a little different spec than a street car.