Help with 99 gt
 

I have the following mods: cold air intake, bigger throttle body and mass air, underdrive pulleys, 4.10 gears, upper plenum, long tube headers. I want to know what other mods can make my car faster..Was thinking about a intake..

Ported heads, cams, NOS, supercharger kit, stroker kit or turbo ...

With what you have already you won't gain much from a new intake, because the stock heads are restrictive. If you can afford it, order a set of the new Trick Flow 2v heads and maybe a set of stage 1 or 2 cams to go with it and then you can think of getting that new intake. That is if you're wanting to keep it naturally aspirated.

Otherwise it's either nos or some kind of forced induction. Check out the Power adder forum for info on how to find and assemble a used novi or procharger kit.

If I get the nitrous, do I need a different intake?

Someone else on here will have to answer that. I have no experience with it, but a few of the members here swear by it.

I have a 99 GT with pretty much the same mods as yours. Nothing really impressed me until I got my nitrous. I have an NX plate kit(wet)- 100 shot. Pulled pretty damn hard the first few times I engaged it....then I smelled the dreaded burning clutch! My car has 80K miles and the clutch was factory...so it was to be expected. Anyways, I just got a new, centerforce clutch(dual friction) and replaced the F'd up factory flywheel. the clutch feels great, but I have to baby it for the 500 mile break in period. Can't wait until its broken in....then I'll need some nitto drag radials....it never ends!

You don't have to replace your intake for nitrous.