I'm not sure if you're already running a supercharger or turbocharger. If you are, you may want to consider a water injection system. There are advantages and disadvantages when deciding between NOS and water injection. NOS will definitely provide a greater increase in power but will dramatically increase the risk of catastrophic engine failure. Water injection will provide a more moderate increase in power (we typically see 40 - 60HP) but will actually provide your engine with immunity from detonation. It really depends on how much boost you are running but a lot of our customers are able to get into one of our systems for $350 which is another benefit over most NOS systems.
We also provide kits for naturally aspirated motors.
Feel free to give us a call and pick our brain about the system.
BTW... I'm not advising against the NOS... just know the risk/benefits of each type of system. Then decide which is more important for your application, maximum power gain or moderate power gain with immunity from detonation.
I can't say for a 302 but we recently ran my 472 (460 0.60 over) on the dyno with a 180hp jetted NOS plate system. On motor we had 303hp and 479ft/lbs torque at the rear wheels, on giggle gas saw 412hp and 602ft/lbs torque. What was a surprise was that we ran it last year with 33" tires, this year change to 35" and I lost 50hp at the rear wheel.
