i believed u will look for a standard / non-mod 1JZGTE for ur project...
so look at the torque band / max torque @ RPM...
coz all the GTE motors r limited to 280hp only...
all the GTE motors also have a very high potential to tune for max hp eg... 600 - 1000hp... n it is depend on how much u willing to spend...
if u want ur car to be more drivable / for daily usage... then u have to look for JZGTE with VVT-i / BEAMS with more drivable torque band...
if u decided to mod it, then u have to look for the MT tranny V160 6sp or R154 5sp to handle the amount of torque this motor gonna produce...
all VVT-i / BEAMS version JZGTE will be widely available at the lastest toy chaser halfcut but mostly r attached with AT tranny...
non VVT-t / standard JZGTE... look for supra MKIV... usually is a twin turbo version with availablity of MT n AT trannies...
usual mod of twin turbo JZGTE is... change it to single big turbo...