Tech:Engine/A Series/RWD Gearboxes
There are 2 main options for a gearbox when it comes to converting your 4AGE to RWD/FR. The choice you make is dependant on how much power you expect your engine to make. The T50 gearbox should hold up well enough under a worked N/A engine provided you treat it nicely. If you have intentions of a supercharged or turbocharged engine, I would suggest you head towards the W5x gearbox option.
T50 Gearbox - You can source a T50 gearbox from an australian AE71/AE86 or get one from an imported AE86. There is 1 main difference between the australian and japanese T50 gearboxes. Both of these should handle stock power without a problem. (These are the 22 spline version, not the celica 20 spline)
* ADM T50 (Australian Domestic Market) - Clutch fork on passenger side of car. * JDM T50 (Japanese Domestic Market) - Clutch fork on drivers side of car.
ADM T50
JDM T50
W5x Gearbox - You can use a W55 gearbox with a bellhousing adapter, people usually swap to these when their engines are putting out high power figures as T50 gearboxes are a lot weaker. Note that you will have to modify your tailshaft to suit the different gearbox output shaft.
Gearbox Bellhousing Adapter
Sourced From http://www.skynet.ie/~eireae86/tech/4A-G_W_bel_housing/