Kelly,
My single EGT probe is just down stream of the turbo. I do my measurements in Celsius. Peak is about 915 or so. I usually climb out ROP and with the reduced RPMs, EGT are in the mid 700's to low 800's. MP on take off is anywhere between 30 and 45" depending on my mood and who I am trying to impress - though I usually try to keep it under 40". Even then it is for only the first 1000' or so, then I usually maintain about 28-30" through most of climb, and cruse at 22-30" depending on my mood. ROP cruse EGTs are 750 to 900 depending on power, RPM and how rich I make things. I usually lean it out just enough to keep EGT's around 870. (that is appx 100 deg ROP). If I am using a lot of boost or flying formation (when I cant keep an eye on the EGT) I will richen it up and keep the EGT's in the low 800's.
I have done a lot of LOP flying. In cruse it is difficult to get the temps much below about 890 without the engine running a little rough (occasional misfire). Climbing LOP is actually better because the lower RPM's really help keep those EGT's down. Descending is the opposite, the EGTs really climb with the higher RPM. That is how I lost turbo #2, a long high-power descent at essentially peak EGT (about 920 or so) (Hey, I was late and didn't know any better - you guys can thank me for doing the testing :-)
I have been on a kick lately to keep my EGT's down so I have been running mostly ROP. At the last annual I was getting some leaking around the stock exhaust manifold. Turns out that the gasket had worn out and that the manifold itself was getting some of the typical cracks that those cast iron manifolds are known to get. It looked to me as though at least part of the problem was oxidation. I replaced the manifold with one I had sitting around, but they have suddenly become harder to find. So my current plan was to eliminate the oxygen in the exhaust and keep the temps lower by running ROP.
The problem is, that ROP flying really uses up a lot more fuel. Yesterday, flying home from Mammoth. I was hitting a headwind and would have maybe had to stop for fuel if I didn't lean it out (ASOS on departure was reporting wiinds 25 gusting 38mph - tough to get the plane loaded and untied in those winds). Anyway, 9 gal/hr LOP will get me about the same power and EGT as 11 gal/hr ROP (different MAP setting). Add more fuel and get lower EGT's but power starts dropping a little while the cost goes up fast. So, I have decided to go back to running LOP during cruse on my longer trips, especially if I fly at lower MAP settings.
-- David Leonard Turbo Rotary RV-6 N4VY http://N4VY.RotaryRoster.nethttp://RotaryRoster.netOn Thu, Mar 10, 2011 at 11:05 AM, Kelly Troyer <keltro@att.net> wrote:
David,
Glad to hear from you..........Reminded me to ask you the same questions about your
turboed 13B as I did John Slade..........
Would like to know your typical EGT's and MP (boost) at takeoff , climb and cruise
and if you lean "lean of peak" (or lean at all)...........
Kelly Troyer
"DYKE DELTA JD2" (Eventually)
"13B ROTARY"_ Engine
"RWS"_RD1C/EC2/EM2
"MISTRAL"_Backplate/Oil Manifold
"TURBONETICS"_TO4E50 Turbo
From: David Leonard <wdleonard@gmail.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Thu, March 10, 2011 12:26:56 PM
Subject: [FlyRotary] Re: Crankcase ventilation
Interesting Idea, though you still probably want some other crankcase vent functional in case the injection ports don't suck enough. BTW, VERY little oil, if any, comes out the vent unless there is something wrong with one of the side seals. probably best to just plug the oil injection and vent the crank case.
-- David Leonard Turbo Rotary RV-6 N4VY http://N4VY.RotaryRoster.nethttp://RotaryRoster.net
On Thu, Mar 10, 2011 at 8:36 AM, Ernest Christley <echristley@att.net> wrote:
I've not provided for clean way to vent the crankcase, yet. And I'm also not going to use the oil injection ports. As I understand it, the injection ports should always be at a negative pressure. Would it be a crazy idea to have the ports pull the dirty air out of the crankcase and not spread it across my airplane's belly?
--
Homepage: http://www.flyrotary.com/
Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html
|