X-Mozilla-Keys:                                                                                 

Paul L wrote: 
The rumors I am hearing about the new Mazda wankel side exhaust port
rotary
to be announced next month is that they have the efficiency up to a
equivalent
piston engine. Even in the low speed car EPA driving cycle.
We shall see shortly.

Paul Yaw wrote:

I would imagine that "recycling" the portion of the charge that didn't
burn the first time around will really pay off, but I don't think that
it will ever compete with modern piston engines.  The Honda VTEC engine
has a BSFC of about .43 tuned for best power.  The Mazda V6 that we
messed with was pretty close to that, but I don't remember the exact
number.  Maybe .45 or .46.  Very impressive!

PY

By agressive leaning at altitude Tracy is seeing 0.47 or 0.48 with the 
rotary which is not that far away from a Mazda V6 piston engine.

It is very interesting to see those numbers Paul. Almost everybody
advocating water cooled car piston engines assumes BSFC is well below
0.40. Actually water cooling is a drawback as running an engine 
at 212 F means  more heat energy is given up to the coolant while
an aircooled aircraft engine will run 300 degrees or above. 

The Continental SAE paper mentioned on the ACRE NL web site
http://home.earthlink.net/~rotaryeng/ on liquid cooled aircraft
engines discusses this factor at length. Continental was
able to get the liquid cooled Voyager aircraft engine 
series below 0.40. 

BTW the number I have for the big block Chevy is 0.53.

Paul Lamar
 
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