My AE86 started as an automatic SR5. The first project my dad and I did together, aside from the basic maintenance stuff, was converting her to a five speed T50. Here's our project on that:
http://www.dorikaze.net/showthread.p...6-5-speed-swap
So my current setup is:
-OEM 20V Blacktop
-OEM Redtop AE92 flywheel and clutch (7.5kg)
-Cusco Engine Mounts (10mm thinner than TRD/OEM)
-T50 5 speed transmission
-Team M factory taller 5th gear, second generation (.737)
-TRD short shifter
-Using redline MT-90 gear oil
-Weir Performance 4.778 Ring and Pinion
-Zenki 2 Way TRD Limited Slip Transmission
The T50 was a huge upgrade from the "3 speed" auto. I say "3 speed" because when I bought the car, the overdrive solenoid wasn't engaging. After spending some time with the T50, it seems that:
-it was originally a 70's 4 speed that TOYOTA simply added a 5th gear to. Poor engineering.
-the gearing is completely mismatched to what a 4age needs. Poor engineering
-one of the two TRD close ratio kits that could fix this mismatched gearing is discontinued and the other is pretty expensive. Boo earns.
-taller 5th gears are available, but are not under regular production. With a 4.78 ring & pinion, highway RPM is at around 4175RPM @110km/hr. Something to consider.
-they don't handle torque well. I lost track of how many T50s the local drift guys went trough each season. Sucks to be you.
-finding a rebuild kit was near impossible until a fellow DK member put together a full rebuild kit including the discontinued caged needle bearings he had custom made to compete the set. Good on ya, mate.
-although parts are getting harder to find, it's a relatively easy transmission to work on. Not bad at all.
So if you want a period correct TOYOTA use a T50, or if you're still saving up for the most logical upgrade, get a J160 6 speed from an 98'-05' Altezza. Or, you could also get a nearly bulletproof transmission from Quaife, but it'll cost you around 7000 British Pounds for the transmission itself without bellhousing or ancillary parts.