Help with my gt engine, engine lacks power Options

[trd-celica]

hi, i need help im trying to make my car as fast as possible with out doing any swaps for now i have a custom msd coil with nology spark plug wires,headers with 2.5 catback exhaust,intake spacer,venom control module,racing clutch and a koyo radiator but my car is lacking power.when i'm trying to accelerate it hesitates at the begining and it does it in every gear. what can it be.

[_mikeE]

^ What he said and get yourself some good suspension, and good tires (lightweight rims if you could afford it), and get your camshafts regrinded by Webcams, 10lb flywheel......................or you could turbo your 5s motor (not exactly doing a swap)