vibration in a troopy

More likely to be something to do with the exhaust system I think.

marts
Sometimes some equipment developes a vibration or resonance at a certain rev range, this is refered to the critical speed range.
I have been involved in all sorts or rotary and other machinery and sometimes you can cure it by trial and error or somtimes you need to just push through the rev range that the problem occurs in and suffer it.

Try checking the vibration isolation points that the exhaust hangs from, on the 78 the exhaust actually hangs in rubber vibration mounts, chech that it has not been knocked of the mounts and it contacting any body or other meteal componant.
It could be as described above a critical speed range in the turbo.

In the end its probably going to be a bitch to find.

Let us know if you do find the problem.

Check the rear pinion. I had the same problem (non turbo) everyone thought it was the engine or exhaust, tyres or alignment. The collapsible spacer collapsed too much and the pinion was loose.

Haven't got your free wheeling hub's engaged have you!

Marts,

Check the exhaust system and see if the mob who fitted the turbo fitted a bracket from the exhaust to the transfer case.

I had a turbo fitted to my 100 series a few months back and when I picked it up the fitter said that the exhaust supplied in the turbo kit was running to close to the chassis.

As a result he fitted a bracket from the exhaust to the transfer case.

At idle the vibration through the car was skocking and at a certain rev range the vibration returned.

I then took the car to the exhaust place who removed the bracket and repaired the exhaust. Problem fixed, no more vibration.