vortech305

Im about to order my NOS kit and before i do i sort of made a mistake, i have all the other essential hardware but in the piston rings department i made a bad decision, I installed Cast SLP(Summit) pistons, i know i should of gone with the moly rings but will the cast rings suffice with a 150 shot? Motor has been rebuild with forged pistons,rods and crank but can i hold out with the cast rings if not whats the highest i can go? motor has about 400 miles on it and yes i know i should wait at least another 1000 to break it in. thanx in advance.

Ions91Z28

edited, read cast pistons... not rings. None the less, I still think you'll be fine.

F-BIRD'88

Detonation needs to be avoided at all cost.
That means using the best available pump gas 92+ octane
and or racing fuel. Be sure you are providing a constant flow of fuel at the recommended pressure. Ignition timing needs to be conservative like 28 to 32. Start at 28.
Use a spark plug that is about 2 heat rangers cooler than stock and brand new. Set the plug gap @ .035/.040". Nitrous doesn't like old plugs. Do not use platinum plugs with nitrous. Other than that you'll be fine.

GTAlover

Don't must F-body's come with forged pistons?

Ions91Z28

GTALover, I don't believe any F-bodys came with forged pistons.

GTAlover

But they come with hydrolic roller cams and they make some many nitrous kits for them. I don't think cast pistons would stand a nitous blast...and I've blasted plenty of nitrous through my stock motor.

B4Ctom1

I cant believe it either, especially when you consider that 5.0's stangs had them from 85 to 92!

Ions91Z28

Cast pistons can with stand nitrous. As long as you keep the shot low, and keep a steady amount of fuel. I've known a guy that shot a 200 shot on cast pistons. Probably 30 plus runs at 10.70s. Fuel is the key with nitrous, also have it nitrous preped as most call it. Fuel and ignition must be set up right.

I still don't recommend it however, when I put it on mine (planning to atleast) I'll only be running 100 shot.

GTAlover

I really really think they came with forged pistons. Summitt seems to think so.

Acceld Z

All thirdgens came with cast pistons. I have a box full of broken stock pistons. Even the ZZ4 crate motors don't have forged pistons. I think LT-1's, Lt-4's, and ZZ4's came with hypereutectics but i'm not 100% sure. That's the best GM's done since around 1973. As long as an appropriate amount of fuel/timing/spark is supplied to the engine, it will survive. If you detonate or run lean, all bets are off.

MouseCamaro305

Acceld Z is right, all 3rd gens did come with cast pistons, and lm not positive about the LT, and LS-1's but the ZZ4's did come with hypereutectics.

Someone once told me that the pistons inside a nitrous motor are not designed merely to "hold up", but rather different pistons can be more or less forgiving. for instance a forged piston can be more forgiving and take more abuse and mistreatment than a hypereutectic, which people claim to be the worst piston for nitrous use, because its a high slicon cast-aluminum piece.

in essence, if a motor is built well and the user understands the limitations on tuning and racing the motor, a hyper will hold up just as well as a forged piston. just don't expect to be able to pay no attention to the fuel level, and not check all 8 spark plugs while running a 150 horse shot of nitrous through the motor on cast pistons, without there being some serious problems.

forged pistons can handle the most abuse

cast stock pistons can handle a fair amount of abuse

hypers are the weakest of the 3, and need to be closely taken care of.

hope this helps, and if you need any further info talk to b4ctom- he's a brilliant nitrous guru