My new piston 3.0+

[Rivet]

Originally Posted by PeteKz

What full-throttle, full-advance timing did you find for max torque?

Pete,

Benefits of full ignition control is to pinpoint the best timing for the full RPM range. That number is dynamic and unique to the fuel choice, ignition control vs actual spark event when ignition control latency isn't calibrated, RPM, and the engine package as a whole. The peak timing number is in the mid 20's in this case.

Michael

[PeteKz]

Mike, thank you for your reply.

I know that the timing is dynamic and depends on multiple factors, but I was looking for a comparison of the timing at a defined condition to compare to the timing typical of a conventional twin plug piston and chamber at the same condition. If your engine is in the mid-20’s with the Apgar piston, then that puts it in the range of the timing of the twin-plug ignition with a conventional twin-plug piston dome. Is that about right? Or does it require several degrees less advance?

Maybe I am not asking the question in the best way, but I am looking for some method of comparison, without having the same engine, but with conventional twin plug pistons, to run on the dyno for a direct comparison. I think that comparing timing is the next best method.

[Rivet]

Originally Posted by PeteKz

Mike, thank you for your reply.

I know that the timing is dynamic and depends on multiple factors, but I was looking for a comparison of the timing at a defined condition to compare to the timing typical of a conventional twin plug piston and chamber at the same condition. If your engine is in the mid-20’s with the Apgar piston, then that puts it in the range of the timing of the twin-plug ignition with a conventional twin-plug piston dome. Is that about right? Or does it require several degrees less advance?

Maybe I am not asking the question in the best way, but I am looking for some method of comparison, without having the same engine, but with conventional twin plug pistons, to run on the dyno for a direct comparison. I think that comparing timing is the next best method.

Pete,

When the hardware allows I do individual cylinder trims as needed so that is why I was ambiguous and mentioned that its dynamic, both this motor I posted about and the comparison motor were timed this way. Also I consider the tune information proprietary to the paying customer.

To give some numeric info though, it has a mean delta of 3-4 degrees less than a full dome piston in a pretty aggressive build on the same regional E10 pump gas.