Power

Both activities will make the car work. The harder you make it work, the more it will eat your gas mileage.. I don't know if I would buy that vehicle looking for power off a red light.

Cut your catalytic converter out pacesetter headers (if made for your year) upgrade exhaust to 2.5" egr delete (google it for your truck a few diy if you're an ok mechanic) more aggressive camshafts (expensive) this will increase torque a bit but it's an epa no no and im not liable for any f-ups