Right here goes that purple nova turbo (Mark Watts one) Ran a F20 box for 5 years and back in 1996 when he got the gear box it only cost him £45. He had a LSD fitted and does track days. Here is the cars spec:-
Vauxhall 2.0 Litre 16 valve Turbo featuring Courtenay Turbo Modified ECU for improved Power and Torque.
Power : 240 bhp
Torque : 245 lb/ft
KKK water-cooled turbocharger with modified actuator and re-worked air inlet path.
16 psi boost pressure electronically mapped for smooth power delivery.
Courtenay Turbo re-profiled camshafts for additional power and torque.
Lowered Compression Ratio.
Internal water flow path modified for improved cooling.
Cylinder head modified for improved crankcase breathing.
Cosworth cylinder head.
Extra large charge cooler with twin water radiators for greater inlet temperature reduction.
2.5" bore bespoke Courtenay exhaust system.
Courtenay 2.5" bore tail box with 4" chrome tailpipe.
Now I would not be arsed changing the gearbox 5 yrs later after a lot of abuse would you? Rick
If I can drop my pennies worth in. I had a Mk2 Astra GTE 16v with 2.0LET and ran 240bhp and 230 lbs and the F20 never gave up, even after loads of circuit outings. The gear change speed is better with the F20 than the F28(In my opinion) and they are cheap to come by.