Ok first off the engine in my 73 mach1 is a 351c, however the are not very many differences in these engines. I was getting ready doing my burn out before i staged, I reved it up and droped the hammer and the car just shut off. Quiet, no big bang, Anyway we tore the engine down, only to find a piston had bashed the valves in the # 5 cylinder. This is not so much my question. We also found that the second ring on every piston was broke off. I was shooting 180 shot of nos when i raced. I didnt use it on burn outs. Was this caused by the nos or inproper installment.

 

well the only plausible explanations for the rings i can think of would be A. rings installed wrong or B. wrong size or defective. or they would have to slide out the cylinder wall and try to go back in and i dont see that happening lol

 

Pistons into valves can really only weak/wrong valvesprings or just overreving it..........
Dunno about ring problems...........

 

As far as rings, yeah, either installed wrong or all bad(not likely, prolly installed wrong, wrong application etc) If it dropped too low in the cylinder the oil control ring would be annihilated as well. As far as piston to valve contact, yeah, you either had the wrong one and floated, over revved it for what they were meant for, or it had fatigue and finally gave. It's unlikely the use of NOS(used correctly) was the culprit

 

What about a jumped timing chain?

 

I wouldnt think youd jump the chain, iv herd of belts but the chains are usually good, i say the odds of that are very slim if even possible.