Bottled horsepower. It used to be that big horsepower increases required major internal engine modifications. However, Nitrous Express has a way that's a whole lot and cheaper.
Just bolting one of their EFI single-nozzle nitrous systems onto your domestic or import can add from 35 to 150 HP to a V8, with intermediate choices of 50, 75, and 100 HP (with a maximum of 75 HP for fours and sixes.) These systems rely on a Nitrous Express Shark performance nozzle and will work with standard fuel pumps, without any timing retard. The kits include the nitrous bottle, nozzle, hoses, solenoids, wiring, and mounting hardware.