First thing is my car is a 78 280 with an LS1, T56, infiniti Q45 R200, with all Johns Cars and TTT mounts.
I had bad vibration at 70+ mph. I rotated the tires and the vibration moved around with the wheels, so I called the shop that mounted them and said I think the balance is off, can you check and fix them? Since I had them mounted several months ago they wanted to charge me again even though it's only been a few hundred miles driven on them. When I had them mounted, I even asked them if I could take it back if I had any problems as I wouldn't have the car driveable for several months. Of course the lady at the counter gave me the oh sure, no problem, but when it came time to deliver she didn't remember that and couldn't find any record of me in the computer. I said screw you guys and brought it elsewhere, and these guys came and said these tires are way off. they ran it twice for me, and said they are all perfect now. I got it out and now the vibration is around 80. The new balancing took over half the vibration out and it moved it up in speed some. At this point I'm going to trust these guys have them properly balanced and move on down the line trying to figure out what's vibrating.
My questions are:
What kind of driveline angles should I have?
Has anyone had any issues with the balance on the driveshaft from Johns Cars?
Do CV shafts have to have a certain angle and is there such thing as balancing them?
What about brake rotors, any such thing as balancing those?
Anywhere else I should look?
The vibration is there whether in gear, neutral, or with the clutch depressed and in gear.