AJ06GT

Eh, but if he rebuilds the top end and is hitting 300 rwhp N/A, then I think a 50 shot shouldn't be too bad.

Actually, you make me think. Really and honestly the best way to get that power is to just sell it and get a 96-98 Cobra. You'll be a little under without mods, but bolt ons should get you there, you'll have a lot more room to grow with the 4v (though you still need the forged bottom end before much over 400), and it'll cost about the same as doing the whole H/C/I swap, or even a lot less if you need someone to do the labor for you. I thought about building my GT, but I realized it's really just a waste of time and got a 4v instead. If I couldn't afford my 03 I would have at least gotten a 96-98. Those are some of my favorite cars. I'd LOVE a 98 Bright Atlantic Blue Cobra. If I find one around here it might replace my 97 as my new DD.

2000GT4.6

With that kinda miles on the engine, I would be looking for a good used low milage 2v PI motor. Starting from theres alot better point than starting with a PI swap on a car with 110,000 miles on the shortblock.

Whats the budget, thats the most important question.