Paul wrote:
Engine durability and power to weight ratio are entirely
different issues. It is going to be hard to beat
the current air cooled aircraft engine in these
regards. Don't underestimate them.
Paul Lamar
Mike Wills wrote:
There is an article in the current Contact about an RV-6A that is Chevy V6
powered. The author (who assembled the engine) indicated that the aircraft
owner was happy with his results. The airplane firewall forward cost was
"under $14,000", the TBO of course is unknown but "could be 1000 hours", And
the airplane empty weight was 1350 pounds. If this is what the owner wanted
I guess thats great, but it sounds to me like he totally missed the mark.
This engine installation cost as much as installing a used mid time Lyc
would have cost and its 300 pounds overweight! In fact as it sits on the
ramp with gas in it (no people or baggage) it exceeds Vans recommended
aerobatic gross weight.
As you said far too many people sell the Lycosaur short. Modern electronic
engine controls could make it the second best choice in a gasoline burning
aircraft engine. :-)
Mike Wills
I think Al Gietzen wrote this and it is probably very important
when it comes to beating an aircooled aircraft engine.
Maybe the direct air-cooled
engines can get by with less flow because their average fin temp is probably
considerably higher than we can accept with a water coolant loop. I had
always heard the liquid cooled was better from the standpoint of cooling air
required. Maybe we need to design for a higher air temp increas
Air cooled cylinder head temps run 250 to 350 degrees F.
Seems to me delta temp is almost everything. Here is a picture Of the
fastest RV6 in the country. Notice the small intake area for
the cooling system. Obviously advances are still being made in air
cooled aircraft engine cooling drag.
If the total intake area of my cooling system (radiator plus oil cooler)
equals this small area I will be very happy indeed.
I would rather work with a fan cooled, air cooled rotary but
the Mazda is the only suitable rotary available so we need to
do the best we can with its liquid cooling.
Paul Lamar
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