Flywheel issue

[akosmo]

Hi everyone,
I'm new to the Rover V8 game. I have a 3.9 Rover V8 out of a kit car. It came with its old SD1 LT77 gearbox and a Toyota Supra R154 gearbox which the previous owner tried to replace it with. In the midst of the gearbox 'replacement', the previous owner lost the SD1 flywheel as he had a custom supra gearbox to rover sd1 flywheel made up.
I have decided to refit the LT77 gearbox. My issue is, I fitted a 9.5" 23 spline clutch to the supra flywheel and fitted the gearbox and new slave and master and bled it all up. The clutch isnt engaging, so I can only guess that the flywheel isnt thick enough and the throwout bearing isnt pushing far enough onto the fins of the pressure plate. The supra flywheel is 27.5mm in thickness from the back face (against the flange on the crank) and the front face (where the pressure plate mounts to)
I have read online that an SD1 flywheel is 31mm. Is this 3.5mm difference enough for it to not engage?

I appreciate any advice possible

Thanks

[stevieturbo]

What do you mean it isn't engaging ? The splines don't engage ? you've no drive ? you can't select gears ? etc etc

Stick a small borescope camera in there to get a look.

[SuperV8]

There are a few similar clutch slave cylinders from various old Landrover/Rovers etc.. with different bores - which might just help give you enough throw - if that's your issue? that you have a firm clutch pedal but the clutch isn't 'disengaging'?

Smaller slave bore will give you more movement - at the expense of making the clutch pedal heavier.
Or bigger clutch master will have the same effect.