Measuring dynamic cylinder pressure

[Shannen Durphey]

----------
> 
> 
> Has anyone ever installed a pressure transducer in the spark plug hole
and 
> run the engine with that cylinder's spark and fuel injector disabled? 
High 
> speed data acquisition would be required, but it would allow one to
measure 
> the effects of various mods (cam, intake, exhaust, boost, etc).  Higher 
> pressure would indicate better cylinder filling, although some
temperature 
> compensation would probably be required.  The max pressure for a
non-firing 
> cylinder is 120 to 200 psi, well within the range of reasonably priced 
> transducers.
> 
> Bryan Zublin
> bzublin at nlvl.com
> 

Since thermodynamics play such a large role in gas flow, would you be
getting an accurate measurement?  How about temperature sensors mounted in
the exhaust/headers at each cylinder?  They might indicate combustion
efficiency.  Hotter gasses=more power.
	I know that cranking compression readings are in no way indicative of
performance level. The only general rule that seems to apply is the longer
the stroke, the higher cranking compression.