The piston burns.

[Ilya2]

Hello, guys!
I'm from Russia. I do have a problem. The piston burns all the time at the NOS power more than 150 HP. The engine specification: volume - 1730 cc (106 c.i.d.), cylinder diameter - 84 mm, stroke of piston - 78 mm, 4 cylinder, compression 11.5:1, gasoline octane +116, ignition less then 20 degrees, 4 throttle bodies (EFI), 16 valve, engine power - 225 HP, technical NOS, system direct port 4 cylinders is used.
Tell me, please, what is standard chemical composition of your technical gas NOS?

[Tom K]

The composition of automotive grade N2O (Nitrous Plus) is Nitrous Oxide (N2O) 99% / Sulfur Dioxide 50-100 ppm.
Thanks, Tom.

[Sanya]

Hi to everyone!
Topic is interesting, 'cause I have the same problem...piston burns at a definite engine power.

Tom K, thank you for your answer.
One more thing to the comment above: air/gasoline ratio 11.7-11.9

I've heard you guys are the best! Thanks for any input.

[Tom K]

Most engines will find their sweet spot around 12.5:1 AFR. You will want to pay close attention to your plug readings including the timing line on the ground strap. Contrary to popular beliefs, a richer mixture is not safe. You will damage a piston faster running too rich than too lean. As long as you pull enough timing out of the engine, a lean tune will result in a loss of power and not engine damage.

Thanks, Tom