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One thing to add. I don't know, but strongly suspect, that the hp numbers are quoted at the rear wheels. There seem to have been several quick reports of less than spec'd hp very quickly, followed by Mazda's revision of the hp numbers. It seems unlikely that several new car owners would all pull their engines out of the car for testing. Most independently run dyno tests I've seen are chassis (drive wheel) dyno numbers.
Do any of our hot rodders know if I'm correct? The point of making that distinction is that shaft hp would logically be quite a bit higher.
Charlie
Ed Anderson wrote:
Jarrett,
I'll take a stab at your questions. First, the HP rating of the Renesis is in a bit of flux. It was orginally listed as approx 250HP at somewhere around 9000 rpm. However, once folks got their hands on some and put the on dynos, it became apparently that the engine did not produce 250HP at least in its stock state. The latest figure I recall was in the vicinity of 230 HP - still not bad. However, if you do a search on the web on Renesis you may find some more recent figures.
I don't think you will find any maximum continous ratings for any of the rotaries. Clearly the higher RPM you run the engine the more stress and wear. I personally have no quams about running the older 13B at 6000 rpm the entire flight, although I normally fly it between 5200-5800 due to the lower fuel burn.
The literature indicates that the Renesis gets apporx 20% better fuel economy - thats the good news, the bad knews is I understand that is only gain occurs only at the lower rpms and that at the rpms we would normally run it at - the 20% gain decreases considerably. No free lunch - you want power, you burn fuel.
Tracy's 2.85:1 and EC2 EFI should work with no problem. The weight of the engine might be a few pounds less than a 13B but nothing significant. The rotors are a pound lighter each and so the counterweights are probably lighter as well, so maybe a 5 -10lb reduction in weight over the 13B block - nothing significant in weight savings like aluminum side housing would provide. I think it uses direction ignition (one coil per plug) so that might save a few pounds over the heavy 13B ignition system. My personal opinion is that you can probably gain the same power out of a 13B if you have the rotors lightened, heavy duty bearings/harden gears and the entire rotating assembly dynamically balanced so you can wind to higher rpms. Would also need the right induction and exhaust system. I mean the racing guys can get over 250 HP with the NA 13B - however, their reliability might be less than you would entertain for an aircraft application.
Lynn could probably address what you can get out af a 13B better than anybody on the list
Lynn??
JJJ here are a couple of URLs on the Renesis that might help
http://www.rx8.co.nz/Rotary/renesis.aspx
http://asmic.com/collect/rotary1999/rotary_e.pdf 36 page PDF on the rotary engine with some stuff on the Renesis
Hope it helps
Ed
Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC
eanderson@carolina.rr.com <mailto:eanderson@carolina.rr.com>
----- Original Message -----
From: JJ JOHNSON <mailto:JJJOHNSON@ACCESSCOMM.CA>
To: Rotary motors in aircraft <mailto:flyrotary@lancaironline.net>
Sent: Tuesday, November 18, 2003 12:19 PM
Subject: [FlyRotary] Re: Renisis
Question for the list. I've seen lots of numbers thrown out there
as to how much power this engine is 'supposed' to produce. I'm
wondering if anyone has some concrete numbers as to how much
'continuous' hp's one can expect at what rpm [what is the max
continuous RPM recommended?]and at what specific fuel burn? Also
can this engine be turbo'd? I understand from the Factory [in the
Rx8] its NA. Tracy's 2.85:1 unit should work on this engine?? As
well as his electronic gizmo's? How far is this engine as far as
weights [installed] from the 13B? I've got lots more but lets
start there. [Or maybe someone has a web link they can pass on
that helps w/ these questions] I apologize if some are these [ I
suspect they probably are] redundant.
Thanks
Jarrett Johnson
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