first v8 on this forum---whoo!

anything can be done to any car its just how much you want to put into it (here is a picture of someone at fastfieros.com that put an ls1 in a gp.

the concept is: why would you want to? other than being probably the only one to do such a thing theres plenty of aftermarket performance for your car as it is---enough to make it much faster than my car.

if its for the "wow" factor, i would love to see someone do it It would be quite a bit of work though.

as for upgradeability--most ls based parts can work in the engine such as cams and such, but its very difficult to get to and can involve removing the engine. all the mods ive done are the easy ones--i still have my warranty to worry about, but there is a cartuning turbo kit being developed that can make these cars very interesting (12.3ish quarter miles, and nearly 500 whp) but the tranny is a weak link much like the rest of the gps, its the a (mildly) upgraded version of the 4t65e thats typically mated with this engine and unfortunately some are on their 5th transmission literally.

so yeah, anything you want can be accomplished, you just gotta pay to play :-/