what engines are making successful aero engine conversions?

On Wed, 20 May 2009 13:15:15 -0700 (PDT), bildan
wrote:

On May 20, 10:27Â*am, cavelamb wrote:
bildan wrote:
On May 20, 2:01 am, Dancing Fingers wrote:
Years ago there was an article in Kitplanes about someone trying to
use a Honda Goldwing engine. Â*Did that ever come to fruition?

I've not heard of it.

Actually, the cylinders, pistons, rods and crank from the Honda 1800cc
Valkyrie flat-6 combined with a aircraft style case would hit the spot
for fans of smaller airplanes. Â*However, it would still need a PSRU.

something like 260 pounds for 80 hp?

I wouldn't think so. The crank is light enough to use as a dumbbell
and that's heavier than the cylinder blocks. Just guessing of course,
but I'd say 180 lbs for 100HP which is better than an O-200.


They ARE heavy because the trans is integral - and the trans does not
handle the prop as a PSRU. One I am aware of lost the gears in several
hours of flying.

On Wed, 20 May 2009 17:59:24 -0700 (PDT),
wrote:

On May 20, 2:15 pm, bildan wrote:
I wouldn't think so. The crank is light enough to use as a dumbbell
and that's heavier than the cylinder blocks. Just guessing of course,
but I'd say 180 lbs for 100HP which is better than an O-200.

The TCDS says the O-200-A is 190 lb. My experience with the engine
makes me wonder about the 100-hp claim. The C-90 I flew had more pull.

Dan

my docs say "rated horsepower" which makes me think that there is a
calculation used to derive the figure not an actual 2750rpm
measurement. the 74hp at 2500 rpm seems to be measured.

On May 21, 5:21 am, Stealth Pilot
wrote:

my docs say "rated horsepower" which makes me think that there is a
calculation used to derive the figure not an actual 2750rpm
measurement. the 74hp at 2500 rpm seems to be measured.

They normally take a brake horsepower reading, with the engine at
redline RPM and full throttle. Torque times RPM times 6.28 divided by
33,000 gives HP.

BUT:
The O-200 makes its 100 hp at 2750. The C-90 its 90 hp at 2475.
Everyone knows that drag increases by the square of the increase in
speed, so the O-200's prop theoretically has 19% more drag than the
C-90's. The C-150's prop is narrower and I think a bit shorter than
the prop on the Aircoupe I flew with its C-90, so its drag might be a
bit less to start with, but overall the losses will still be higher at
2750.
So adding RPM to gain hp is a poor way to go. That's why PSRUs
are better than direct-driving a tiny prop at 4000 RPM. And it's also
why a 110-hp Corvair, if it's running at 3300 or some such RPM, isn't
going to outdo an O-200.

Dan

"Stealth Pilot" wrote in message
...
On Wed, 20 May 2009 17:59:24 -0700 (PDT),
wrote:

On May 20, 2:15 pm, bildan wrote:
I wouldn't think so. The crank is light enough to use as a dumbbell
and that's heavier than the cylinder blocks. Just guessing of course,
but I'd say 180 lbs for 100HP which is better than an O-200.

The TCDS says the O-200-A is 190 lb. My experience with the engine
makes me wonder about the 100-hp claim. The C-90 I flew had more pull.

Dan

my docs say "rated horsepower" which makes me think that there is a
calculation used to derive the figure not an actual 2750rpm
measurement. the 74hp at 2500 rpm seems to be measured.


The rated power is achieved at standard sea level temperature, pressure and
humidity; and is also a maximum permissible limit, even when the combination
of temperature, barometric pressure and humidity might enable the engine to
produce more power than the maximum for which it was certified.

Bob schreef:
I think the topic (40hp engine) is of sufficient interest
internationally to justify some form of permanent address on the
internet. The problem is only going to become worse.

Well here goes for what it's worth: a certain Mr. Doutard from France
fitted a reduction to the 2-cylinder Citroen Visa car engine.
Unfortunately he passed away some 6 year ago and I could no trace of a
follow-up. The idea seems excellent though. Actually there is one such
engine in my car right now but of course it is not on offer.

The guy in France from whom I got it had heard rumours of some Italian
doing much the same thing, with the extra addition of a turbo-charger.
That seems a bit weird on a 2-cylinder boxer... Who knows more?