> > > > 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
Here are some better shots of the intake manifold Paul is using.
I am not surprised it is not as good as the three carb set up
used by Tracy in the early days and now owned by Finn Lassen.
Basically it is no manifold at all. It is mainly an
adapter that adapts the dual throat TB to the Mazda block.
Paul Lamar
Atkins also makes a wrap around manifold that puts the Throttle
body on top of the engine which I think would work better, or you
could use the stock 13b lower manifold section and the Racing beat
upper section as the Atkins throttle body is the same bolt pattern as
the Weber.
Ken Welter
That is TWM throttle body Ken.
http://www.twminduction.com/faq/throttle_body_faq.html
I don't think he makes the manifolds either. Probably Racing Beat.
Paul Lamar
Hi, Ken....I purchased the wrap-over intake from Dave Atkins, but it put the
TWM throttlebody too high....I would need a huge football sized bump on top
of my cowling. I exchanged it for the short straight intake manifold. It is
cast aluminum and has the Atkins Rotary name as part of the casting. The
wrap-over manifold, however did not have the Atkins name anywhere on it.
Paul Conner
I saw a Y wrap over like that today at Mazdatrix. It has been around for years.
Page 15 1985 Racing Beat catalog. There is a better version with out the "Y"
in the 2000 catalog. Individual runners. Also in the 1997 MazdaTrix catalog
page R10 and R11. If you don't need turbo clarance they have a very nice four
runner lower 90 degree man. You will need a set of runners to go along with
it.
Paul Lamar
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