>>  >>      The five blade warp drive only weighs in at 18 lbs and
I am sure a
 >>  >>  damper will work but if a heavy flywheel gives a better climb rate
 >>  >>  than the extra weight is paying for it self.
 >>  >>    With the heavier flywheel I noticed that it lifted up on
the step in
 >>  >>  the water better and better climb performance and like I said Atkins
 >>  >>  reported the same gain on his RV.
 >>  >>    Also Skip Gorman reported better performance on rotary
boat engines
 >>  >>  and said that there is no way he would run without a flywheel.

 > >>  >>

 >>  >>     Ken

 >>  >I am surprised a heavy flywheel gives a better climb rate. In theory
 >>  >there is no HP advantage. Less torsional vibration I'll buy. The
 >>  >rotary already has
 >>  >a lot of rotational inertia what with the two nine pound cast iron
 >>  >rotors and balance weights. Dave Atkins has never flown one of Tracy's
 >  > >gear boxes to compare. BTW Flywheel windage losses can make
a difference
 >>  >at 6000 to 9000 RPM. The stock flex plate has a few fins on it that
 >>  >should be removed.
 >>  >
 >>  >Speaking of heavy flywheels take a look at this EngineAir V8. It
 >>was the only
 >>  >way they could get the gear box to live with out a torsional
 >>  >vibration damper.
 >>  >
 >>  >Paul Lamar
 >>  >
 >>
 >>     A flywheel will absorb power spikes and then give them back in
 >>slack times.
 >>    In the VW sand world I run a flywheel, a full circle counter weight
 >>  crank and a 11 lb front pulley all to get more weight to absorb the
 >>  pulses and with that it climbs the dunes better and turns better
 >>  times in the 1/4 mile.
 >>     In the snowmobile world they make heavier flywheels and they also
 >>  climb the hills better and pull harder on the flats.
 >>    If you simply put a rubber damper in there the power pulses are
 >>  absorbed but little is given back, I do like the rubber damper idea
 >>  but I think it needs a flywheel also.
 >>     The cog belt is a very good damper but I found that a 16 lb
 >>  flywheel with it worked out the best and I think about 16 lb with a
 >>  rubber damper on a planetary would be about right.
 >>
 >>     Ken

 >Well Mazda reduced the weight of the RX8 flywheel to improve the
 >engine acceleration. The lighter weight rotors also helped. What
 >a heavy flywheel does in theory is store energy in the form of
 >rotating inertia.
 >
 >If you rev a drag racing engine to 5000 to 9000 and step off the
 >clutch the energy stored in the flywheel will be transferred to the
 >wheels in the form of instant HP. If you just drive away you don't
 >get max torque until the engine can rev to the torque peak.
 >
 >In the case of the RX8 most people don't rev the engine to 6000 RPM and
 >step off the clutch. In that case a lighter flywheel allows the engine
 >and car to accelerate faster. Particularly while in the lower gears when
 >the RPM climbs rapidly. (I spent 30 years in the car performance test
 >equipment business :))
 >
 >Paul Lamar

    Your right the light flywheel does rev quicker in the low gears in
 the 1/4 mile but the heavy flywheel pulls harder in the last of third
 and all of fourth gear.
    The punk street racer kids like light flywheels because they are
 snappy but the people winning races are running heavy ones.

    Ken

There is nothing in the physics books that say anything about that other
than impact theory. The shape of the torque pulse has little
to do with the HP out of the engine (consequently the weight of the flywheel)
as long as it does not go negative. Unlike a four cylinder four cycle engine
the torque pulse of a rotary never goes negative. All that matters is the area
under the torque pulse curve. Add that up and you get the mean torque (HP) out
of the engine.

In an aircraft engine, powered by a 2 rotor, four torque pulses per prop rev
are applied to the prop with a 2:1 gear box. Are you saying the prop
RPM speeds
up and slows down four times per prop rev? Are you saying that the speed
up and slow down of the prop results in less mean thrust out of the prop?

Paul Lamar

   Without the damper when I pull back on the stick to climb the rpm
drops very noticeable and with the damper there is very little drop,
also it just climbs up on the step quicker but there is no way to
measure that.
  I am not saying that it is like bolting on a turbo or anything but I
think the flywheel more than carries it own weight and the dampening
effect is a bonus.

   Ken

 
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