Greg
Ward wrote:
>
> O.K., time to throw a little F
matter into the fan. I am sitting in my new shop, with a Lancair Legacy RG,
and a relatively new 20B "D" series on a palette. I got the engine complete
with everything it had in the Cosmo that it came out of. There isn't even a
coat of grease on this thing. Radiator, oil cooler, air conditioner,
condenser, ECU, injectors, coils, motor mounts, and about 100 pounds of
extra stuff came with it. My buddy (he has been selling engines for 15
years) in LA that sold me this engine ($4500.00) is in constant contact with
people who race this motor, and I am getting a lot of input on how to set
this thing up. I have ordered Tracy's gear drive, and plan on generating 400
HP on take -off, and about 75-80% at cruise. My max rpm will be 8000. You
have no idea how much input I am getting from the racing set. They are
saying that with a variable boost (electronic) controller, I can vary the
boost at any given altitude, as much or as little as I want, and tweak this
thing for max performance. They can't believe that I am asking so little
from this engine.
>
> This will get us
started;
> Greg
> Greg, I don't want to rain on your
parade, but there are three questions you have to ask
yourself:
- Can I reliably pull that many horses out of
the motor for hours on end?
- Can I carry enough fuel to support
pulling that many horses for hours on end?
- Can I keep the engine
from melting while pull that many horses out of it?
It's
been demonstrated on this list several times that not everything from racing
translates directly to airplanes. For instance, 400Hp will require twice the
radiator volume that most of us are using, along with the larger associated
ducting and cooling drag. Will the reduction in reliability and increased
fuel burn be paid for by the extra speed once the effects of the extra
weight and cooling drag are factored in? ie, you will go faster, just not as
much as "double the Hp" would imply, because of the cooling drag. I don't
think most racers have to worry about that to much, but you could wind-up
with a system that just cost you more to go to only relatively close places
faster.
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