OK...I'd suggest forged pistons for sure, SRP makes some really good ones at a reasonable price; and try some GM powdered metal rods - they come stock on all the motors since 93, and they're actually stronger than the old forged 'pink' rods that GMPP used to sell.
Nitrous doesn't care about compression, at least not as much as blowers and turbos do, so you can run whatever compression you want. Pump gas will limit your compression before the nitrous does.
You'll need an aftermarket ignition and some cooler than normal spark plugs. I'm running Autolite AR94 race plugs, but they're kind of high maintenance. NGK TR6's give good performance and reasonable plug life.
Don't use platinum plugs. They tend to hold heat and will cause detonation in a performance motor, nitrous or not.
Cam-wise, all power adders like a wide LSA, lots of advance, and lots of exhaust duration.
Crane has some specific grinds listed in their online cam catalog. I would imagine Comp does, too, although I'm more of a fan of Crane.
Heads - A couple of things. How dedicated are you going to be to the juice? Most head building books I've read suggest when running any kind of power adder to worry more about the exhaust side than the intake. David Vizard goes so far as to suggest fitting the biggest exhaust valve you can in the head, and then choosing the intake based on the room left after you pick the exhaust valve. He goes on to say that a dedicated power adder head should flow between 80 and 100 percent of the intake flow, on the exhaust side, depending on how much power you're adding. The other thing is valves. You're going to be running a lot hotter, so pick the best valves you can afford. Are you going to be running aluminum heads? If so, make sure the head deck is extra thick to handle the added cylinder pressures. Vizard (can you tell I like his book?
) suggests 3/4" thickness on the deck, minimum.
HTH,
