Zero clearance side seals round 2. (If you don't mind Barry)

[Barry Bordes]

Originally Posted by 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.

ninesixtwo,
Actually that is the approach that I have been working on. The TFX program also does Fraction Burn and Combustion Rate.
Anything that we can do to increase burn rate is beneficial....

One thing that can be done without internal mods (hint) for instance would be experimenting with ignition split and it's effect on burn rate.
The saw tooth angle of burning gases and the fraction burn shown below have been used to make definite increases.
Barry

[Barry Bordes]

Originally Posted by Barry Bordes

ninesixtwo,
Actually that is the approach that I have been working on. The TFX program also does Fraction Burn and Combustion Rate.
Anything that we can do to increase burn rate is beneficial....

One thing that can be done without internal mods (hint) for instance would be experimenting with ignition split and it's effect on burn rate.
The saw tooth angle of burning gases and the fraction burn shown below have been used to make definite increases.
Barry

Compare the above Fraction Burn and Combustion Rate rate to the result achieved in this much later experiment.
You can see the dates of each test in the top left corner.
This total increase happens by many very slight incremental improvements.
Barry