the clutch can cetainly take 250nm of torque, thats far more than a 172.. true capability is probably 3-350 nm.. its got a built in shock absorber for drive takup too and turbo load, should be great with nos.
I have just measured the clutch clearence and I dont think you could put an adapter plate in AND use the turbo clutch
... you could certainly have the 6 speed with std flywheel / clutch though..
the ratios are overall the same as the 5 speed with an extra gear between 4th and 5th,, nice !!.
another option..
I have enough parts to build the following unit
turbo f4r block
turbo crank
rods
172 pistons
turbo head (non vvt)
turbo cams
172 induction system
vandervell bearings for crank.
all new gaskets, seals, turbo head gasket, new cambelt etc.
oil spray jets for pistons.
Comp ratio 10.5:1
6 speed box - bolts straight on ! - no mods needed.
turbo clutch assembly with torque shock.
you should be able to use your exisitng throttle body - or maybe a slightly larger one.. and your ecu could probably be remapped by Nick Hill when he gets the rollers.
that would be a pretty entertaining combo with nos !.
to assemble and supply the unit, box and clutch would be about 2.4k complete.
that would be from a new block / crank etc.. new box.. new clutch..
I can offer no guarantees of easy fitment of the unit to your car, however, I cannot see any real problems.
Joe.