REFLECTOR:Rotary 20B dyno Test
J.P. Brooks
reflector@tvbf.org
Sat, 10 May 2003 14:18:52 -0700
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Great news!
Best of luck.... seriously.
JP Brooks
DeltaHawk, Inc.
At 01:32 PM 5/9/2003 -0600, you wrote:
>Rock on, rotory guy. Very impressive results, and I'm envious of how
>silky smooth it's going to be when you get airborne.
>
>Dennis Martin
>Elite FG Chevy V-6
>
>>
>>I've completed dynamometer testing of my 3-rotor rotary engine. Overall;
>>I'm very pleased. Great performance from a normally aspirated engine
>>where the all-up installation weighs maybe 45 lbs more than a 200 hp
>>Lyc. It should give me about 270 HP at my max operating point of 2900
>>prop speed. The following is a post to the rotary engine list (including
>>a response from a rotary Guru), and a plot of sea level torque and
>>HP. More info will eventually be available on my website.
>>
>>Al Gietzen
>>
>>POWER AND TORQUE
>> >
>> > Wide open throttle power and torque curves were run after adjusting
>> > the mixture correction table and the timing. Mixture setting was
>> > approximately for maximum power. Data was initially gathered up to
>> > about 6000 RPM, but looking at the data showed that the torque curve
>> > was still flat, and hp increasing, so subsequent runs were made to
>> > 7000 RPM. Still no break in the hp curve. Given that the 2.17 redrive
>> > ratio limits engine RPM to about 6300 (Prop @ 2900), there was no
>> > point in pushing things further.
>> >
>> > The torque curve is distinguished by it's flatness; varying only by 10
>> > ft-lbs from 210 ft-lbs at 4000 rpm to a peak of 220 ft-lbs at 5000 -
>> > nearly constant from 4800 to 6800. The 220 ft-lbs is not
>> > extraordinary, and could be improved by 9.7 compression rotors vs the
>> > stock 9.0 rotors that are in the engine. Mazda's data indicates about
>> > a 4% increase in power with 9.7 vs 9.0 at 5000 rpm. It may also
>> > improve some as the engine wears in - this is an engine with only a
>> > couple of hours of running since overhaul.
>>
>>The 20B is going to make one hell of an aircraft engine.
>>I can't wait to see one of these engines in an air race.
>>The Lycoming weenies are going to wonder where the severe head wind came
>>from :) And this is only 87 HP per rotor at the benchmark RPM of 6000.
>>
>>Paul Lamar
>>
>>
>>
>>Attachment converted: Macintosh HD:power - torque1.gif (GIFf/ogle) (00022A41)
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Great news!<br>
Best of luck.... seriously.<br>
JP Brooks<br>
DeltaHawk, Inc.<br><br>
<br>
At 01:32 PM 5/9/2003 -0600, you wrote:<br>
<blockquote type=cite class=cite cite>Rock on, rotory guy. Very
impressive results, and I'm envious of how silky smooth it's going to be
when you get airborne.<br><br>
Dennis Martin<br>
Elite FG Chevy V-6<br><br>
<blockquote type=cite class=cite cite><font face="Verdana" size=2 color="#0000FF"> </font><br>
<font size=2 color="#0000FF">I've completed dynamometer testing of my
3-rotor rotary engine. Overall; I'm very pleased. Great
performance from a normally aspirated engine where the all-up
installation weighs maybe 45 lbs more than a 200 hp Lyc. It should
give me about 270 HP at my max operating point of 2900 prop speed.
The following is a post to the rotary engine list (including a response
from a rotary Guru), and a plot of sea level torque and HP. More
info will eventually be available on my website.</font><br>
<font face="Verdana" size=2 color="#0000FF"> </font><br>
<font face="Verdana" size=2 color="#0000FF">Al Gietzen</font><br>
<font face="Verdana" size=2 color="#0000FF"> </font><br>
<font size=2>POWER AND TORQUE</font><br>
<font size=2>></font><br>
<font size=2>> Wide open throttle power and torque curves were run
after adjusting</font><br>
<font size=2>> the mixture correction table and the timing.
Mixture setting was</font><br>
<font size=2>> approximately for maximum power. Data was
initially gathered up to</font><br>
<font size=2>> about 6000 RPM, but looking at the data showed that the
torque curve</font><br>
<font size=2>> was still flat, and hp increasing, so subsequent runs
were made to</font><br>
<font size=2>> 7000 RPM. Still no break in the hp curve. Given
that the 2.17 redrive</font><br>
<font size=2>> ratio limits engine RPM to about 6300 (Prop @ 2900),
there was no</font><br>
<font size=2>> point in pushing things further.</font><br>
<font size=2>></font><br>
<font size=2>> The torque curve is distinguished by it's flatness;
varying only by 10</font><br>
<font size=2>> ft-lbs from 210 ft-lbs at 4000 rpm to a peak of 220
ft-lbs at 5000 -</font><br>
<font size=2>> nearly constant from 4800 to 6800. The 220 ft-lbs
is not</font><br>
<font size=2>> extraordinary, and could be improved by 9.7 compression
rotors vs the</font><br>
<font size=2>> stock 9.0 rotors that are in the engine. Mazda's
data indicates about</font><br>
<font size=2>> a 4% increase in power with 9.7 vs 9.0 at 5000
rpm. It may also</font><br>
<font size=2>> improve some as the engine wears in - this is an engine
with only a</font><br>
<font size=2>> couple of hours of running since overhaul.</font><br>
<font size=2> </font><br>
<font size=2>The 20B is going to make one hell of an aircraft
engine.</font><br>
<font size=2>I can't wait to see one of these engines in an air
race.</font><br>
<font size=2>The Lycoming weenies are going to wonder where the severe
head wind came from :) And this is only 87 HP per rotor at the benchmark
RPM of 6000.</font><br>
<font size=2> </font><br>
<font size=2>Paul Lamar</font><br>
<font size=2> </font><br>
<font face="Verdana" size=2 color="#0000FF"> </font><br><br>
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