If you’re running a carb, I’d think about using a carb built for nitrous. Besides the points that bjuice touched on I think the carb is often an overlooked part of building an engine for nitrous. With the proper tune up nitrous will make more power and some serious heat which of course attracts the dreaded detonation monster. Due to the increase in fuel needed for n2o you’ll need to speed up the burn rate via ignition timing events etc. and a professional built nitrous carb which is fitted with a custom fuel/nitrous curve. (Better fuel atomization, even fuel distribution and detonation eliminating signals to help keep you from lean conditions). Don’t let anyone tell you there is no difference in carbs or no such thing as a nitrous carb. Just ask the big dogs.
Also, I’m not trying to butt heads with bjuice (I agree with all his points) or anyone else for that matter, but when selecting a cam you might want to try thinking outside the box and do some research on using a cam with tighter LSA. With today’s cylinder head technology and the exceptional work some of the cylinder head gurus are producing it may be of an advantage to delay the intake opening and delay the exhaust opening without changing the exhaust closing point. (tighter LSA) What’s the advantage? Here’s what one of the big dogs has to say. Pay close attention.
Patrick Budd from ProCar explains it this way: (if using a PG)
“The solution may lie in providing the engine with more ability to accelerate via shorter timing events, helping it pull up and away from the shift on its own. A slightly tighter LSA (removing the duration from the exhaust opening pulls the centers slightly closer- we have no beef with the exhaust closing point) will also set up a hard accelerating engine through the upper- midrange. The last thing a nitrous fed engine wants to do is sit at a steady state, and anything we can do to help it accelerate up from the rpm drop on the 1-2 will pay off in et and reliability.
By trimming timing events to the minimum, we’ve arrived with a combination that runs harder, more predictable, and with greater reliability.”
Think about it! This nitrous stuff isn’t rocket science but it’s not a walk in the park either. When using nitrous its important knowing what you don’t know or it can become costly due to lack of knowledge. I do hope Tom or Ed or Curtis will chime in when time allows.
Good luck,
John