Latest update - I still running with a harsh vibration between 65 and just over 70MPH.
So far the gearbox mount, propshaft and rh rear wheel bearing replaced - all had differing degrees of wear but none have solved the problem.
What I know is :-
One of the rear wheels has oval stud holes, the tyre shows signs of uneven wear.
The spare tyre was uneven giving a worse vibration, new tyre has fixed this.
The other wheel and tyre seem ok now and swapping sides does not alter the vibration, but its still there.
Checked the wheel bearings on each side yesterday, slight play possible grumble on the LHS, but I am not experienced enough to know, slight endfloat of less than 1mm, checked the new bearing on the rhs, about 3mm play arrg[xx(]
I have spoken with Robsport, looks like the play is too much, but the problem is not likely to be the Diff as there is not reaaly any whine, no banging and the prop seemed very straight when tested on the ramp. Main suspect is wheels but I have now almost covered this.
I am now looking at replacing the LHS bearing.
Didnt mention that in the meantime th RHS front bearing failed and has been replaced.
I think I am getting somewhere but it seems 1 step forward and 2 steps back. [:(!]
Pete
1981 Carmelian Red 2 litre DHC - out for the summer.
Polybush, KYB shocks, electric fan, electric windows and electronic ignition roller bearing struts and anti-dive kit - otherwise standard
1979 Pageant Blue Spitfire 1500 - In hibernation - Engine overhaul needed.