[ninesixtwo]

Aiming for a certain peak chamber pressure vs a given crank angle is fine in theory as most people don't have access to in-cylinder pressure monitoring so its kind of a moot point. In practice, OEM level calibration involves monitoring the crank angle at which 50% of the combustion charge has been consumed. The optimal point for CA50 has a 2-3 degree range for any engine, whereas peak cylinder pressure can be deemed "optimal" for a range more than twice that.