So, i found a website (
http://www.suprastore.com/2jzgteengine.html) that sells Supra "mods". One of the things i was looking at is the new engine replacement. Any opinons/ comments? (6speed manual btw)
I've owned both a 06 GTO and several Supras, get the Supra.
It is a special vehicle that has timeless looks, is very rare, and has the reliable power that you want.
GTO's are awesome cars too, especially the 05-06 models with the LS2 engine. They are much more common, and some people aren't very fond of the subdued exterior styling. Some don't like the fact that they aren't a true "retro" muscle car, but rather an imported Aussie Holden Monaro with a Pontiac badge.
The GTO has a better interior than the Supra, the seats are much more comfy, and the layout is real clean and modern. Although it could be argued that it is an unfair comparison seeing that the Supra is about 10-15 years older than the GTO.
Power wise, stock for stock the GTO wins, but thats because it has more HP. Upgrading potential goes to the Supra because it is a turbocharged platform with a stout engine block that can handle a lot of power.
If you know you're going to mod the car, Supras offer a better bang for the buck comapred to the GTO. It takes several thousands dollars in bolt ons for the GTO to achieve the power levels the Supra can create with simple BPU mods, most of which you can buy used for cheap on this forum. The GTO bpu mods are usually intake, long-tube headers, exhaust, and a few other mods, most of which net around high 300-400rwhp. But after that, the only real way to achieve power above 500hp is to go FI, nitrous, or built engine.
Simply put, the GTO is a heavier, less aerodynamic Corvette.
It's subjective, but if I were to choose, seeing that I've owned both cars, and not a biased fanboy, go with the Supra.