Do you think this is caused by the short rod ratio or maybe the high CR and your getting detonation?

_________________
67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

I did the same thing to one with nitrous. I would guess detonation. I also split the piston in two.

_________________
Official Cookie and Mater Tormentor.

I thought the 2.2L piston was a very strong one. Maybe is just a strong one compaired to it weight.

_________________
67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

Hyperteutectic are stronger than cast, but are supposedly brittle. I raised the top ring lad on 3 other pistons besides the one that let go. It was from being too rich on fuel when spraying.

_________________
Official Cookie and Mater Tormentor.

My understanding is that too lean is the bad one when on spray. (I know very little about nitrous though)
Stock piston is cast Aluminium? (weakest cheapest)?
The 2.2L pistons are hypereutectic silicon and AL (stronger more costly)?
Forged piston are steel? (strongest, heavy,costly)?
Does this sound right.
If you were to have a custom piston made for a low rev engine that can handle lots of nitrous, what would the piston material be?
Don't concider cost unless its Nasa priced.

_________________
67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir

What few people realize is that too rich on fuel is almost as bad as too rich on nitrous. Rich on fuel cuts power, but lifts the top ring land, even on forged pistons.

Forged pistons are aluminum. They are just machined from a forged blank instean of a casting.

_________________
Official Cookie and Mater Tormentor.