Russell Kent wrote:

Paul wrote:

This is a four rotor so divide everything by two.

So that gives a BSFC of 0.289 ? Cool.  ;-)
[Note for the humor-impaired: I am poking fun at Paul's
over-generalization.  I know the 2 rotor BSFC won't be twice as good as
the 4 rotor's.]

Russell

Yea, don't forget this is a racing engine. As Tracy Crooke always
says when he gives his talks "you want a manual mixture control because
sometimes you want max power".

I think by placing the injectors up on the intake end of
the ram tubes the BSFC will be reduced over these numbers at
the same power levels. Mazda had the injectors near the ports
on these engines. Also the trick that Everett used I.E. mounting
the butterflies near the port will help the low speed running
of a Lemans type peripheral port engine.

BTW I also forgot to mention that urban lore on peripheral ports
was gathered in the old days when people were using carbs.

I suspect a venturi as used in a carb has a limited range of airflow's
over which it will properly meter fuel. Obviously if it is too
big the velocity is too low to suck enough fuel and the engine
might go lean or the fuel may just dribble out and not evaporate
completely or mix throughly. 

I think, probably, the same thing can be said about a 
mechanical fuel injection system to a certain extent as the 
dynamic range of one single mechanical injector is questionable.
This may be the reason Everett chose a smaller intake tube
and peripheral port.  

With a modern, staged injection system like Tracy's I think we will not
have that problem. A peripheral port engine with EFI and Everett's 
modifications should run fine at low RPM and power levels.

Further improvements in BSFC may be possible by using the Fisch high
pressure injectors as now used on OMC two cycle outboard engines. 
Perhaps squirting fuel directly into the compression chamber after the 
intake port closes may be the hot tip.
 
Paul Lamar
 
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