Quick hp gains question
 

I bought my 02 GT apx. 2 weeks ago and have been wondering if like the 5.0s; is there any free (or dirt cheap) hp tricks(ala removing air silencer and adding k&n filter.) Already added the k&n and already had exhaust. Thanks in advance

You can always remove the air silencer, but I don't think it really does anything. By taking it out, you will get a bigger opening, but the stock setup does a nice job of taking in cooler air from the fender well.

Air filers can only do so much too.

Power ain't cheap. If you want it, you need to pay for it. Biggest bang for the buck is gears and they don't in reality add any hp, but your car will be the equivalent of about 40 hp faster.

want quick easy power... two words BLOW ER. there is nothing but suspension and brakes that are cheap to toy with and deliver good benefits. Power adding is an expensive and not usually easy thing to do if you're looking for a decent return on your investment.

gears and computer tune

If your '02 GT is a 5-speed car, ECM tuning will really improve the low and midrange torque. There is a significant delay in fuel enrichment for open loop in this year PCM.

How much boost can he put to the stock bottom end and for how long?

I wouldnt run more than 8psi through the stock block... if you have the supporting mods, that will equal around 400 hp which is also the max HP you should be running with a race tune. youd want a lesser street tune for daily driving.