Vega

Was wondering if it might be safe to run nitrous on cast pistons. Not a huge shot of course and everything would be rebuilt and reconditioned. Just a thought, figured if anything i might answer this question for a few other people on a budget

was thinking for a 455 (i sometimes forget that people build other Olds than that, its a terrible habit, i appologize lol), or in a 350? Honestly im not really planning anything, but if i finish my build and at some point get bored with the performance it might be nice to know if i could do this or not to add some pep. Ive heard of Pontiacs running nitrous on cast pistons but Olds may be a little different. Not sure. Cant hurt to ask at least haha

BIGJERR

Why a cast piston when the after market for Olds forged pistons is now flooded with options? i wouldnt build a performance engine without forged......So I guess i wouldnt run nitrous on that set up,Why temp fate? Will it work ? sure for a while.......I stopped retarding my timing running a 125hp shot years ago,Never burned a piston but finally the bearings went......The problem with nitrous is its like crack.....Just a little turns into something more.....Bolt on horsepower in addicting!

Vega

I'll be working with cast pistons is why i asked. I picked up a set of high compression stock pistons for my 455 for $50, sure beats $450 for forged haha. I especially wanted to run stock pistons since the bore would allow it. I dont like over-boring if a motor doesnt need it, in a Chevy sure go ahead but in an Olds? Theyre getting rarer and there were only so many built, if you dont need to bore it you should leave it stock. Also i figured id ask cause im sure there are those folks out there with a stock motor thinking "hmm, wonder if i could bolt this on without tearing down my motor" haha. It was just a thought really, im not planning any of that at the moment, just looking for a good mild build. I didnt think about the addicting part haha, i can definatly see how it would get like that. You use it, then again, and again, and suddenly its not "this makes my car go faster when i have it" instead its "my car goes slower when im out" xD

Eh, i think i'll wait. After thinking about it, its not really something id wanna do at the moment anyway

Lee_A

Be sure to increase the gap on the top rings.

Run to Rund

Carry a bag of oil-dry to clean up the street after the engine blows up, lol. Nitrous gives a more or less vertical torque curve and is very hard on parts.

Vega

Okayyy, i get it, its not advisable haha. Was just wondering if it might work and what recommendations to follow if i tried it. I'm not planning it but later i might consider it. I know Pontiacs have run over 100 shot on cast internals. For right now a big block will be more than enough power but i figured id ask in case i thought about it later, or to answer this question for anyone else who might wanna know.

Lee_A

It doesn't matter what brand or type of piston, or the make of the motor, you WILL break something if the top ring gap is not "right". The nitrous is going to put a lot more heat into the chamber, the top ring is going to expand further from that heat, and if it expands enough for the ends to butt - either the ring will break, the ring land will break, or you the crown of the piston will break.

MOST motors will have a little "cushion" in the ring gaps, but if you don't measure, then you are gambling.

matt69olds

I think you can get away with it. Keep it around 150 hit, make sure you retard ignition timing 2 degrees per 50 hp of nitrous, and make sure the fuel pump can supply the required fuel. Even if the engine doesn't require it I would run some race gas whenever you plan to push that little blue button. Race gas is expensive, but MUCH cheaper than shattered pistons. Open up the ring gap like mentioned before.