1) 89 Colt GT has subtle body kit that is nice good brakes short ratio tranny if you want it nicer interior than the base models and GL power options.... thats all I can think of.

2) I have no idea what a 4G15 is... only guess is that the Colt E has a 1.5 in it from the factory... is that its model designation?

3)As far as I know and I dont know it all the non turbo Block crank rods head intake manifold intake valves and valve springs are the same. 7.8 pistons are easy to come by (I have some) Cams too (I have some with gears). SS valves are about 13 bucks a piece ( I have stock turbo valves too ) There is a guy in TBDSM who put a complete N/A head minus cames on his GSX. Its running great so far. hmmmm... I dont know about the throttle body. ummmm.... MAFS is different. uhhhhh.... thats it I guess.

call me for a deal on stock 4G63 turbo parts.


p.s. what are you doing?