Low gear, low speed vibration

[FTA1995]

Hi again guys,
I'm having a little trouble figuring this out. I've been getting a nasty gut wrenching vibration anytime I open it up in 1st gear that tracks the trans-back rotation speed, its only like that in first. I also need to take into effect that I have moly lower control arms, torque arm, and track bars along with edlebrock shocks, all with poly bushings with a solid cowling. I believe the springs are stock height. Does this sound like a u-joint problem or maybe incorrect suspension geometry under high chassis load?

I think I'm starting to understand that there is never a correct answer to a problem, just a different less problematic mechanical solution.

Thanks again for the help

[Joe 1320]

Might be the pinion angle. Is your torque arm adjustable?

[Jeff_in_Atl]

It seams like I remember seeing someone else with a LT1 and a vibration issue and it turned out to be something with it needing tuning. plugs, opti, wires or something like that. Just a thought, not suggesting.

[FTA1995]

No joe it's a fixed angle.... I believe a relocation kit can give me a slightly adjustable angle to set.. Jeff, that is a good thought, I had that problem when I got the car from an opti missing the cyl #7 contact inside the opti that is quite the different vibration.

I also forgot to mention I do have a pretty messed up clutch as well, but its mostly the pilot bearing that has issues (very very noisy). Pinion angle was my first thought though.... Its a very deep frequency vibration which points me to the u joints... I'll take a look along with measuring my pinion angle. Also going to buy a relo kit for the torque arm this week (was going to do it anyways before this came up)