A cammed GT is pretty darn fast IMO. I remember mine when it was N/A, car moved out very well....I especially liked 2nd gear and it kept me happy.
It was detroit that really pushed me to go further....these darn 400-500HP cars...STOCK cars...was just too much. And look now, im just now EVEN with a STOCK 06 Z06 vette.....crazy how much power they are giving cars stock now days. Its just nuts....but you know what, what I have now is MORE than enough to keep me happy.
When I was cammed only, I actually never ran into anyone on the street that I couldnt beat. And now that im turbo I have already ran into a camaro that gave me a darn near even run....and a WRX that probably would have beat me or gave me an even run. Point being that no matter what you do, you will almost always run into people faster than your, or just as fast.