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Hi Jim,
Since I removed the turbo, I also removed one blade from my Ivo Magnum. It is 68" electric. NA I'm getting 5800-6000 rpm static at fine pitch. But my tuning is out since my EGT are 1800F at full power. On takeoff I have seen 6500-7000 rpm. At cruise, pulled way back I was at 5100-5200 rpm and getting 140 Knots on the GPS. I'm sure the numbers will improve when I start adjusting the computer in flight. My pitot plumbing was leaking and I was not getting any accurate readings. But this was also my first cruise flight without any engine tuning.
I'm also very serious to put together a PP engine. For NA you can't beat the power and simplicity. Paul Lamar got on the engine he put together for someone 240 HP on the dyno the first try. From other rotary web forums, I'm seeing the same numbers. People are concerned with rough idle. But we don't care about it, since we do not idle at 7-800 rpm like a car. My hangar mate races rotaries. He told me he run a PP once, and the engine starts waking up at 5000 RPM. After that it really starts going. That's about where we want to be, specially if you have the 2.8 drive.
Overall you'll get turbo performance for much less money, 30 pounds lighter engine and no risk of destroying it in a flash. There will be power loss at altitude comparing to the turbo, but I cam live with that?
Buly
CZ MK IV
On Nov 28, 2006, at 1:15 PM, James Maher wrote:
Buly,
I'm seeing about 5680 RPM at liftoff and climbout with the IVO Magnum 72"dia set to about 80" of pitch.
That is at 110-120MPH.
Are you also using the IVO?
What numbers are your seeing?
What is your configuration?
Thanks,
Jim
Bulent Aliev <atlasyts@bellsouth.net> wrote:
Jim, thanks for the report. Aluminum as a heat shield is not a good
idea.My first straight exhaust cracked all over in the second hour of
running.
If I did not have a stainless heat shield, its likely I could have
burned something or worse? I always use 0.016 gauge stainless for the
heat shields.
Try running your engine at night at full throttle with the cowling
off. You'll be surprised :)
What RPM are you running on TO?
Bulent "Buly" Aliev
FXE Ft lauderdale, FL
http://tinyurl.com/dcy36
On Nov 26, 2006, at 5:32 PM, James Maher wrote:
> Yesterday I finally got around to the post 1st flight inspection on
> my Delta.
> Checked all the controls, skins, airframe stuff and then removed
> the top cowl.
> Everything looked great until I got to the muffler.
> The muffler was fine but the heat shield between it and the intake
> manifold was MELTED!
> About a 4" x 4" hole directly above the center of the muffler with
> gobs of aluminum slag in the bottom of the cowl.
> I believe that the heat shield got hot enough to droop and then
> contacted the muffler surface and was history after that.
> It's a good thing that the plenum (also aluminum) did not melt and
> get sucked into the intake.
> That would have ruined my day.
> I fabricated another piece of alum and wrapped it up around the
> plenum this time to prevent it from contacting the muffler.
> This is a temporary solution at best.
> I have an idea for a more permanent one but did not have the
> material on hand at the time.
> With temporary fix completed I proceeded to fly the second test
> flight.
> The OAT was 60F, 10F degrees higher than the first flight and the
> engine acted accordingly.
> The coolant was up to 212F and stable by the end of the runup.
> Luckily the oil was only about 170F so I proceeded to takeoff.
> Climbing out at 110-120MPH the coolant temp was 212F with the oil
> coming up.
> After level off at 3000 feet the coolant eventually came back down
> to a more comfortable 190F with the oil about the same.
> My eyes were almost glued to the EGT though, because I was
> concerned about another meltdown. The highest EGT that I noticed
> was about 1580F.
> I kept the mixture a little richer than last time hoping to keep
> the temps down.
> After circling the airport for over a half hour I decided I better
> land, as the I was loosing the sun again.
> I turned base and final too short, so I was high and fast (flying
> the pattern at 120MPH takes a little getting used to),
> But I did have 9000 feet of runway below me so I managed to get it
> down but not in the first 3000 feet like last time.
> It was more like the second 3000 feet.
> Any other airport it would have called for a go around.
> But it wasn't a bad landing and I didn't break anything.
> Didn't have time or light to look under the cowl after this flight
> as it was already well after 4:00PM ( I hate standard time).
> Can't wait to get the airplane back to it's home airport.
> An hour and a half is just too far to drive.
> Jim Maher
> Dyke Delta N11XD 13b (2.1 hours flown)
>
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