One must be careful when applying race car technology to aircraft
engines. Cars need low speed torque while that is of little importance
to aircraft engines. What matters in aircraft engines is the HP >generated
at max prop RPM.

I think Jim would tell me the same thing. We are pretty much on our
own when it comes to tuning rotary engines. That doubly applies to
turbo installations. Car turbo's are highly compromised by the need
for low RPM torque and good throttle response.

Then of course there is the high duty cycle durability issue of aircraft
engines verses low duty cycle car engines. Car engines don't come
close to the continuous HP requirements of an aircraft engine. That
of course is an entirely different issue. Just thought I would
mention it :-)

Paul Lamar

mike h wrote:

Ultra - high HP racing engines get rebuilt after most every race - not a
very cost effective solution for an aircraft. How many race cars DNF due to
mechanical faiures? Not acceptible in an aircraft (unless you LIKE testing
your ballistic parachute regularly :)

After all, the main reason folks are using auto engines in A/C is for
reliability & cost, right? What other reasons would there be, especially
considering the additional work to convert them?

Mike Harrington

It is not a foregone conclusion that piston auto engines at the power level
required of aircraft are more reliable. Now a rotary on the other
hand is quite a different animal.

Able Ibarra told me he gets as many as 30 runs on his 700 HP turbo
13B. 185 MPH under 8 seconds in the 1/4 with a 2000 pound stock
steel bodied car with ballast in the front bumper no less. 
It is true.  Piston engine cars in his speed class usually overhaul 
the engine after just a few runs.

Paul Lamar
 
The AirCraft Rotary Engine NewsLetter.              Powered by Linux.
ACRE NL web site.
http://home.earthlink.net/~rotaryeng/            http://www.linux.org