the 4AGE is not a good candidate for a turbo setup. A 4AGZE would make a much better candidate due to it being reinforced for the supercharger duties.
You could get a 4AGZE swap, throw some HKS cams, intake-exhaust, etc.. and be looking at some decent HP depending on which GZE you get. OR if you want more power out of the GZE, you could go the twincharger way and add a turbocharger to the supercharger.
OR you could say screw that 4AGE/4AGZE setup and go for a 3SGTE swap from an MR2 turbo or a Celica ALL-TRAC plus a 3SGE transmission from a camry, add a heavy duty clutch and you got yourself a nice 200-250hp + ride.. right out the box. Now can you imagine the HP you could pull after doing some work on that 3SGTE??