Paul wrote:
Hi, fellow rotary enthusiasts....today I took my 13b powered SQ2000 canard up for it's second test flight. Today's flight was much more relaxing, as I already knew (from flight one) that the
aircraft would fly. I took her up to 2500 feet and just flew around for a while, watching water and oil temperatures, tried a few steep turns and did a little sightseeing (All within gliding
distance of the airport). It was 64 degrees F today when I took off. During climb, my water temp climbed to 185 and oil climbed to 182. Once I leveled off, temps settled in at 167 for the water and
164 for the oil.
With the new intake manifold, I was able to go to WOT on takeoff roll and left it there until reaching 2500 feet, where I leveled off for cruise. I'm beginning to be more
convinced that I may be over propped. (64 x 78 3-blade Performance prop). I could only get 4800 to 5000 rpm's both in climb and in cruise. I throttled back to 4400 and the cruise speed was rather
disappointing at 140 knots with the gear still down.
I nosed her over slightly and IAS quickly went up to 180 knots, and flight controls felt positive with no slop in the controls. Engine ran
smoothly and after shutdown, no oil or water leaks were found. It was nice to just hop in, fire it up and have a simple, turn-the key and go fly experience for my second flight. I need to get up to
altitude next and do some stall testing soon, but would rather concentrate on getting the rpm's higher.
Even Tracy and Finn got higher RPM's with carburetors, so I highly suspect the prop. The
rpm's max out at just beyond 1/2 throttle setting, and advancing the throttle further yields no increase in rpm's. The engine still runs smoothly, both at the 1/2 throttle and WOT positions....just
maxes out the rpm's at 4800 to 5000.
My idle is set too low (900 engine rpm's) and after landing, I found that the engine had quit. I rolled off the active and attempted a restart....nothing. Engine would turn over, but would not
fire. I suspected flooding, so I turned off the fuel pump and advanced the throttle to WOT and within a few blades, it fired right up, then I turned the fuel pump back on and returned the throttle
to idle and taxied back in.
Hope this was not too boring. Paul Conner, Mobile, AL
I say it is the manifold and not the prop. I would change the manifold before
I would change the prop. I will design a manifold for you. I am sure Ed Klepies will
weld it up for you if you wish. We can make it ground adjustable
with sections of rubber hose and hose clamps. Is your engine a four
port or a six port.
Do you have a mixture monitor (O2 sensor) in the exhaust pipe? EGT gages?
Manifold pressure gage? All essential for tuning the engine.
Could be something as simple as pressure drops across a filter or hot
air intake. Send me some more pictures of the intake system.
Paul Lamar
Paul, What is the diameter of the butterflies in the TWM throttle body you
have?
Perhaps Dave Atkins will give you your money back if you complain long and
loud enough? I don't know what Ed K will charge but I will design it for free.
Vance, what do you think of this prop?
Too bad Dave did not send you this TWM intake manifold.
Paul Lamar
Paul wrote:
Hi, Paul....you really have my curiosity peaked.....the picute you sent of the TWM manifold with the 4 straight stacks with fuel rail and pressure regulator....Do they make one like that for a 4
port 13b? Light weight, simple, fits in my cowl, etc. Would that give me more power? Paul, need more power, Conner
No they don't but it might be adapted. Cost as much as a custom.
Fit in your cowl is one thing but to get power it would probably
be too short. You need to bend those tubes up a bit and get more length.
On second thought If you are going to stick to that stock cast iron exhaust
manifold we might be able to design a more or less straight tube
manifold that droops down into the strake. How wide is that exhaust manifold?
BTW you are using a MicroTec computer as I recall right? Are the wires from
the throttle position sensor hooked up to the computer? Does the wire
from the O2 sensor also go into the computer?
Paul Lamar
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