Paul,

Just wanted to say thanks for helping me to get in touch with Daryl
Drummond.What a great guy.He is extremely busy but is very interested in
your p-port design.He is gone to a race for about a week but I hope to
fly down and talk to him when he gets back in town.

You mentioned you may put Mark's engine back on the dyno to play with
the RWS EC2. Just curious if that was still in the works when you aren't
so busy on your place.

Thanks again,   Geir

Well it depends on the work load of Mazdatrix. Dave Lemon owner and
crew is  at the same race as Daryl. It is the SCCA national run offs
in Topeka Kansas. Many rotary engine race cars both 12A and 13B
are running.

Probably won't happen as Dave will have a lot of stuff to do when
he gets back. Also it is very difficult to tune the engine
for the dyno load using Tracy's EFI system. Read very expensive
and time consuming. Several thousand dollars or $600 dollars a day.

The dyno puts full  load on the engine at all RPMs while a fixed pitch
prop load does only at static, climb out and max speed RPMs. I suspect
an entirely different fuel map is required. Tracy's system
is best tuned in the air under actual flight conditions. As such it
works well. At least this was the situation when we dyno ed the engine
the last time. Dyno runs are very hard on an engine as we would have
to let it sit there at full power at 200 or 300 RPM intervals while we
fiddled with the mixture. One screw up too lean and you might get
detonation.

I would feel more comfortable with a more traditional EFI system
that takes mass airflow into consideration.
Mass air flow, RPM, and intake manifold air
temperature. A carburetor measures mass airflow
using the venturi. As I see it the manifold vacuum
can vary as the load changes at a given throttle setting
and fixed RPM.

Tracy has made some improvements lately in auto tune mode
so perhaps his latest system would work better on the dyno.
I don't know.

I could be totally wrong about all this but this is the
impression I got from fooling with it for a few days on the
dyno. To prove it one way or another would take a lot more money.

I am sure Daryl has a dyno. Maybe he will build one of these
p-port engines and use his preferred EFI system and find out.
However I kind of doubt it as most racers don't bother
with EFI and use  Weber carburetors which they have a lot
of experience tuning. He might be willing to dyno
your P-port engine if you are real lucky. The low coast Teflon slide
throttle should be of real interest to him as traditional  mechanical
slide  throttles are very rare and very expensive.

Paul Lamar ...No rotor no motor.

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