> > This BSFC claimed is a new worlds record for any engine including
   the best
     > > diesels.
     > > If you believe this crap I got a bridge I want to sell you :)
     > >
     > > Who needs vacuum remelt, forged, 4340 chrome molly steel, shot
   peened rods
     > > and crankshaft used in real aircraft piston engines when
   powdered metal
     > > and cast iron will do ? :)
     > >
     > > http://www.vestav8.com/FAQ.htm <http://www.vestav8.com/FAQ.htm>
     > >
     > > This outfit is giving Chevy a bad name.
     > >
     > > Paul Lamar ...No rotor no motor.
     >
     > Paul
     >
     > This must be the engine that uses muffler bearings allow the
   exhaust
   gas to
     > spin better:)
     >
     > Doug in Nippon

   Hi Paul, Doug -

   Normally, I'm just a passive reader, but on this I have to do more than
   just agree to your comments.

   A long time ago while researching engines, I learned that one gallon of
   gasoline burned per hour can produce 15 usable horsepower [That is
   .4 BSFC. See the enclosed chart from Fayette Taylor "The Internal Combustion
   Engine Theory and Practice which is the bible of the internal combustion
   engine. IMHO it is more like .5 BSFC] at the power take off end of a piston
   engine.


   Theoretically, a gallon of gasoline has
   enough BTU heat to equal almost 50 HP if 100% efficiently utilized. But
   because of heat losses in various forms, it has become history that a
   high-efficiency gasoline-burning piston engine (30% is high efficiency)
   puts out usable 15 HP per gallon of gasoline burned per hour.

   If any piston engine burns only 8 gph, do not expect more than 120 HP
   coming from it. And most of the time, it is 5% or so less than that. I
   have read articles from another engine builder (their market is
   fuel-injected marine Chevy small blocks) that their engines burn holes
   in pistons at BSFC of .39. I take it that mixture is too much lean at
   that ratio and burns much too hot for aluminum pistons of a working
   engine.

   I have to see third-party dyno verification before I believe that 8 gph
   will put out 190 HP.

   Thanks,
   Mike Jerger
   Colorado Springs

   I agree with the rest of what you say Mike.

   Paul Lamar ...No rotor no motor.


Either too lean or too rich..  Running peak EGT will be good BSFC but
also mean high piston temps.  Running either leaner or richer would be
fine (cooler).  Running leaner yields better BSFC than running richer -
as long as the engine isn't misfiring.  Leaner is harder to accomplish
because the change in power with mixture as one leans beyond peak EGT is
very steep - small changes in mixture yield large changes in power.  You
need fine and precise mixture control to each cylinder.  Most engines
aren't setup very well for this.  Paul posted the curves for a
carbureted big bore Continental (O-470S) which are especially horrible -
because of the log-runner manifolds, the front cylinders run much richer
(but poorly atomized) than the other four.  The FI big bore Continentals
are relatively better.


I basically agree with everything else you mentioned..


Regards,

Matt-


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