Hi sidewinder, the bottom part of the Protec rear shocks are 42mm dia the collar is 54mm dia and the threads are 45mm dia.

Thanks for that Don. Sorry just been so busy this week, haven't had time to look at the car, let alone open the engine cover!

Ta!

SAS

New to the site so please bear with me - Could we not build a set of 1.9 shocks as follows http://www.protechshocks.co.uk/build-a- ... ed-bush-19 and fit those as this would give a few more mm's

bump anyone have an answer to the above

Im A coupe owner so take this with a pinch of salt, hopefully the libra/spyder owners will pop in soon, but from looking at the pictures on page 4 I do not think there would be the room for a standard 1.9 shock from memory the springs are 1.9 diameter on the libra and the dampers need to be quite thin to miss wheel/tyres as to where it mounts on the hub. Plus it would be a rather long damper required due to where they mount, as Im sure someone would have done this by now if it was an easy option.

Neil

Brian - Short answer, no. Longer answer, would be impractical as then you would probably have the spring itself going past the wheel rim/tyre edge which would make the clearance issue worse. Notwithstanding the fact you'd need a really long spring which would be liable to bow under compression also the long piston would be a weak point.

To fit a standard config 'short' damper (like on the fronts) you'd need to move the bottom damper mount point (that normally sits right on top of the top arm) up above the top of the tyre for clearance sake. You could do this by bolting/welding some sort of structure on top of the top arm but strength would become an issue given the dimensional constraints in that area and the loads/forces acting on it.

Also that would change the damper/arm geometry I think, perhaps adversely(?).

SAS

Thanks lads I did think it was too simple a solution but I did look at the pic of the new shocks and they looked like a normal Shock. So if I renew my rear shocks I will have to order GTM spyder specific ones from protec.

If you look at the libra ones, the rear ones need all the extra length at the bottom to clear the wheels/tyres & none at the top. Also i just measured mine & they are 620mm long which is longer than the options given when choosing the length.
The front ones need extra at the top otherwise the collar/ spring will hit the wishbone. I think, this is one of the changes Protech made to them.
There may be other reasons as well?
BTW the Protech libra ones are 2.25" diameter springs not 1.9". My old Avo's were 1.9" - both will fit.