Since we had a rare sunny day up here in  Seattle, I went up flying for
an hour after going through the mode 3, 6, then autotune and then a
little touch up in mode 9, on the ground. It was running  pretty
smooth, but still does not like full throttle- maybe it's still a
bit lean up there, but I'm thinking that maybe the Hushpower is too
restrictive- I'm flying on  60% throttle, tuning with the mixture
knob and the EGT is running around 1700, RPM is ~5000, MP- Damn,
forgot to note- maybe 17"?. Funny thing, the coolant and oil is down
around 110 f at these settings. Definitely need to block some of the
cooling air. I don't know if the Dynon airspeed needs calibration, I
did not have my GPS today, but was only getting about 110 MPH at
that throttle setting. I did get one thing accomplished- I
calibrated my AOA on the Dynon.

I'm starting to think about making my own very simple, robust muffler
out of 321- pretty much a straight 2" tube within a 4" tube, with
some holes and a few very firmly welded baffles. I'll try to get   a
drawing out and see what everyone thinks about it.

At least no one called the tower to report an aircraft in distress this
time.

Brian Trubee

I doubt the muffler is the problem. Unless of course it has already
failed
internally. You can look inside with a Home Depot or Harbor Frieght
bore scope.

What is your fuel pressure again?
What size fuel line are you using? It should be AN dash 6.
How many gallons an hour are you burning?

How are you with electronics Brian?
A data acq system would go along way to take out the mystery.

My plate is over flowing from here to the end of April but
after that I will be able to help.

Paul Lamar

My fuel pressure is 37-39 psi, fuel lines are AN-6, and I was
burning up to 10 GPH, and that was at a reduced throttle setting of
less than 60%.

Next nice day I'll go up and get more data recorded.

Brian Trubee

It is a big mystery why that is not working. I am really exploring
the outer limits here. What size wire are you using for the injectors?

With a injector pulse width monitoring system we could check to be
sure an increase in fuel programmed into the computer actually
results in an increase in fuel injected.

Here is one way to do that. You need a CAS simulator. What that does
is tell Tracy's computer the engine is running when it is not really
running.

The other thing that is handy but not essential is a hand vacuum
pump you can buy in the auto parts store. This can tell the pressure
sensors in Tracy's computer they are getting signals from the
manifold pressure when they are not.

Here are a few jpgs on the subject.
The 555 oscillator simulates the engine running and is connected
to Tracy's CAS pin.

This is a very simple circuits and the parts
can be bought at any radio shack. Hire an electronic nerd high school
student to build it for you. Put a help wanted add on the HS bulletin
board.

This company sells all sorts of small low cost kits.
http://www.jaycar.com.au/kits.asp

If you look long enough you might find a 555 Osc
or AKA function generator.
http://www.web-tronics.com/kit-23.html
http://www.amazon.com/Function-Generator-Kit/dp/B0017Y486K
http://www.fishersci.com/
http://www.elenco.com/

Here are a couple of useful magazines.
http://www.nutsvolts.com/ from the US
http://www.epemag3.com/ from the UK

Remove the injector from it's holder and let it squirt into a
glass measuring cup.

Paul Lamar


Brian,

I take it you have checked the basics; like that the throttle blades are
actually going to 100% open. When I worked for Detroit Diesel distributors and
we ran truck engines on the dyno, we connected air box (manifold pressure) and
exhaust manometers. You have to make sure you get the right manometer
connected to the right places. 40" water on a turbo engine manifold and it
would blow the water out as soon as the boost came up. For the exhaust, you
need a few feet of teflon lined hose to take the heat. I forget the allowable
exhaust pressure, but it is not much. You should be able to check exhaust back
pressure on a ground run-up. If needed I think I can look up the specs. A
quick call to a Detroit Diesel dealer should do it also. They should tell you.

Dale Davies