a GA16DET with more then 220whp? possible but not worth the money (in my opinion). hotshot's (either the only or one of the only companies to even provide a turbo kit for the GA16DE) turbo kit only pushes about 160hp
http://lion.esosoft.net/hotshot.com/...bovsstock.jpg. and the kit cost $3739. this is already on 7psi. for 220whp not using nitrous, you'd need to install forge pistons, forge rods, new cams, head work, with FMIC, new injectors, fuel pump, reprogrammed ecu or e-manage (or stand-alone), and a damn good exhaust. plus all the electronic goodies. i'd predict about 220-250whp if this set up was built and tuned extremely well. almost anythings possible, i'm sure there's probably some way to take the GA16DE to 300hp. but look how much money you'd already spend just to get to 220-270whp. 4000 hotshot turbo kit + 800 (pistons and rods) + 500 (cams) + 600 (headwork) + 700 (FMIC with piping) + 400 (new injectors) + 150 (fuel pump) + 1000 (reprogrammed ecu or e-mangae) + $600 (good exhaust and piping) + 400 (electronics) = $9150 (grand total). plus some of these prices are without shipping and you also need to look at labor. WHY? when you could just buy an SR20DET and get about 400hp out of it with about 1/2 the money.
well i hope this made sense and helped!!!