Mailing List flyrotary@lancaironline.net Message #36985
From: Jerry Hey <jerryhey@earthlink.net>
Subject: Re: [FlyRotary] 240Hp?
Date: Sun, 13 May 2007 15:53:57 -0400
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
The report I read a long time ago stated the rpm to be 7500 not 6000. It did not mean much to me since it was with a carb and Mazda Trix's intake manifold.     I would think 215 hp at 6400 rpm (same as PowerSport) would make most people very happy.   I can see no reason why it cannot be easily achieved.  Extrapolate from there to 7500 rpm.    Jerry


On May 13, 2007, at 3:32 PM, Ed Anderson wrote:

 

I'm inclinded to agree, Tracy.  I believe PowerSport claimed 215Hp for their P port installation - which appears realist.    In fact, assuming 100% Ve and a best power A/F ratio of 12.65 it looks like you would need to turn over 7500 rpm   to get 240 HP. 
 
You can further enrich the mixture and pick up some additional HP, and perhaps get a Ve greater than 100% with some induction/exhaust tunning, but still seems a bit much to get 240HP at 6000rpm without forced induction. 
 
I also found this message fragment regarding the dyno test, I presume that Mazdrix/Lamar will put this mod into production given the potential market for it.
 
"Mazdatrix recently dyno’d a N/A peripheral-ported 13B for Paul Lamar at 250hp @ 6000rpm, running a carburetor.  That is an easy 125hp/rotor, and 250 hp from a 195# engine."
 
 
In my research, I pulled up the data on the 4 rotor race engine that Mazda was so sucessful with which used a PP and slide throttle (similar in concept to Paul's) and adjustable  telescoping inlets to tune the inlet to the engine rpm.  This engine also had 3 spark plugs per housing and 10:1 compression rotors. 
 
 The attached graph (apologize for its quality - but, best I could do)  shows that at 6000 rpm (power oriented settings rather than fuel efficient settings), the engine produced a total of around 360KW which equates to around 482 HP.  So given 4 rotors are producing that it would equate to 482/4 = 120.5  HP/ Rotor. 
 
 Assuming it scales linearly - then 2 rotors should give 241 HP at 6000 rpm.  Interesting that Paul's  engine does better at 250 Hp than  produced by the Mazda racing team without the 3 spark plugs, telescoping inlets or 10:1 compression rotor.  Humm,  Perhaps the racing teams should consider hiring Paul.
 
That said, unless you have/know  the actually conditions under which the dyno test is being done and the points the data is taken at, there is simply  a lot of room for "interpretation".  
 
Ed
 
 
----- Original Message -----
Sent: Sunday, May 13, 2007 12:02 PM
Subject: [FlyRotary] Re: EC2 smoke question

Outstanding is right.  It's so outstanding that I tend to put it in the same category as the other info he has dispensed  (I.e., smoke).   I could be wrong though.  All things being equal, the P Port motor should make more power than the sideport engine.  Just not sure it is THAT much more.  Everet Hatch was able to make a little over 210 HP at 6000 with carefully tuned long p-port runners after much R&D.  I do believe those numbers.
 
 
Tracy
----- Original Message -----
Sent: Saturday, May 12, 2007 9:49 AM
Subject: [FlyRotary] Re: EC2 smoke question

In a message dated 5/12/2007 9:20:56 A.M. Eastern Daylight Time, atlasyts@bellsouth.net writes:
240HP at 6000 RPM.
 
That is outstanding HP, even on a California dyno. Any port pictures or porting open and close figures?
 
 Sounds like the one to replicate. A typical Weber intake system from a race shop would be quite short. Not ideal for 6,000 RPM. Better at 9,500 to 10,000 RPM,
looking for 335 HP.
 
Lynn E. Hanover 




See what's free at AOL.com.
<4 Roto Powers.jpg>
--

Jerry Hey STOL 701



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