Just a bit of feedback about suspensions - after much research on this and as many other sources I could find, I decided to replace the whole suspension on my 1993 3.8 with the Dinan stage iii suspension.
All the work done by the excellent (though not cheap) guys at Birds in Uxbridge.
The new components comprise:
new springs
new bilstein gas shock absorbers all round
front camber plates which add about a degree of negative camber to the front wheels
adjustable anti roll bars front and back
With the anti roll bars set in the middle setting at the back and front I can report the following as back to back as I can with the stocj suspension:
turn in much crisper - whole car feels much lighter and more nimble. Much less roll and understeer has dissappeared - the whole car goes where you point it.
slow speed bumps/bump absorption seems much the same - perhaps a little harder
High speed ride has suffered, however, and is now much more "knobbly" - I can feel everything through the wheel that previosuly got smoothed out underneath. However, it now makes 70 mph feel even more like 40 - the faster this cart goes the more it likes it and whilst this was always the case with this car - it is even more so now.
A track day beckons soon - I will see how much it has changed the track handling - much improved I hope but I will report soon.
I am also trying out a set of Pirelli P zero corsas - amazingly grippy tyres - but a bit expensive - the fronts were half worn after one day at silverstone.