As former 92 n/a owner I know about that cars weight & power "problems". Check Dean Marcum's mods out. They are available on one of the Supra websites either
www.supras one of the other clubs: nesupras.org. Dean posted 13.8s-13.9s with this setup.

There are NOS kits available for this car too. Dean? He's since converted to turbo. If you are adverse to such surgery, this car is a great cruiser, predictable handler, with plenty of good looks & enough creature comforts for long road trips for two. It is what it is.