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NoDOHC · 07-11-2010, 07:53 PM

Sorry about the confusion, I thought the same thing that others did, this was a simple transducer installed in the leading spark plug hole.

From what I have seen, there is more available power by building that peak pressure earlier in the cycle. If you are seeing detonation with earlier pressure peaks, 45 degrees is what you get. (This really isn't too bad, at is equates to 30 degrees on a piston engine. As I recall, 12-15 degrees is the sweet spot for peak cycle efficiency (on a piston engine). The rotary may be different.

Actually, now that I think about it, the rotary has a longer combustion chamber and probably requires longer for the flame to propagate. This may mean that the pressure will spike too quickly is it is initiated any sooner, while taking too long to propagate if initiated at this time.

Anyway, I hope that you are planning to analyze the effects of leading/trailing split. Some claim that it makes a big difference, I found no change on the dyno at all for pretty much the entire test.

In fact, I unplugged the trailing plugs and saw no change under 6,000 rpm.

07-11-2010, 07:53 PM	#37
NoDOHC The quest for more torque Join Date: Sep 2008 Location: Sheboygan, Wisconsin Posts: 855 Rep Power: 18	Sorry about the confusion, I thought the same thing that others did, this was a simple transducer installed in the leading spark plug hole. From what I have seen, there is more available power by building that peak pressure earlier in the cycle. If you are seeing detonation with earlier pressure peaks, 45 degrees is what you get. (This really isn't too bad, at is equates to 30 degrees on a piston engine. As I recall, 12-15 degrees is the sweet spot for peak cycle efficiency (on a piston engine). The rotary may be different. Actually, now that I think about it, the rotary has a longer combustion chamber and probably requires longer for the flame to propagate. This may mean that the pressure will spike too quickly is it is initiated any sooner, while taking too long to propagate if initiated at this time. Anyway, I hope that you are planning to analyze the effects of leading/trailing split. Some claim that it makes a big difference, I found no change on the dyno at all for pretty much the entire test. In fact, I unplugged the trailing plugs and saw no change under 6,000 rpm. __________________ 1986 GXL ('87 4-port NA - Haltech E8, LS2 Coils. Defined Autoworks Headers, Dual 2.5" Exhaust (Dual Superflow, dBX mufflers) 1991 Coupe (KYB AGX Shocks, Eibach lowering springs, RB exhaust, Stock and Automatic)