Missing the Big Show

This is the first year I've completely missed Oshkosh, in I don't know how many years. It's kind of a sour grapes pity party, but that's the way it is.

Last year I flew a friend and his C-182 up there, so it wasn't like I wasn't connected or anything, but I realized one of the best things for me was to just hang around the Quickie and see how many moths are drawn to the light.

So, this year I decided if the Quickie couldn't make it, I wouldn't make it. That's completely okay with me, but nothing beats being at Oshkosh with the plane on the flight line, Sandy nearby, and visiting with all the friends I've made over the years.

Next year, for sure.

Third Flight

Quick report.

Flew this evening for .6 hrs. That puts me well over an hour now. I just climbed and circled the airport.

Roll trim is still kattywhumpuss, but that's just hardware work. Also I'm not getting enough elevator down, again easily fixable and the two are related.

I started gently fooling around with the mixture mapping in flight. I am using Deem's lamda meter, which is really cool. I didn't go through the whole thing, just making some mixture adjustments when I happened to look at the meter.

I don't have anywhere near the speeds I'm used to, I think the best airspeed I saw was around 160 mph.

I did check out the airspeed/differential pressure. In level flight and throttle at 2,500RPM I was showing about 93 mph. If you look in the table, in the previous post, you will see that is only about 4 inches of water. Not enough, I think. I should probably be getting at least 5 1/2 inches, so that will be something for me to work on.

I'll report back when I know more.

P.S. I apologize to someone. They left a constructive comment and I accidentally hit the reject button and I can't take it back. Sorry. Please post it again and I'll try to not be so clumsy.

Starting the de-bugging

Now that I proved that it can fly, I need to get after all the squawks. Right now, the main issues are engine heat and power. Yesterday I went out and:

1. Adjusted elevator push rod for better roll trim.
2. Significantly opened up the path for cowling discharge air.
3. Discovered air leak around #2 cylinder. Will repair after next test flight.
4. Took care of fuel line chafing on cowl.
5. Plumbed in an airspeed indicator to measure cowling pressure differential.
6. Hooked up mixture meter so I can observe it in flight. I will continually be checking the fuel/air ration to fine tune the EC3 mixture mapping.
   

It started raining so I didn't fly.

Regarding item # 5 above. There are a lot of factors about engine cooling and there are several great articles out there if you are willing to search for them.

One of the fundamental things to check for is to make sure that you have an adequate pressure differential between the top of the engine, compared to the bottom of the engine. The engineers like to refer to this as inches of water, as seen in a manometer. Let's say you had no baffling at all. In that case there would be zero pressure differential and zero inches of water.

Lycoming wants to see between 5 1/2 & 6 1/2 inches of water. Since rigging up a manometer can be cumbersome, there is an easier way, using an airspeed indicator. I had an old one laying around so I hooked it up kind of like this (scroll down a bit).

If I don't have enough pressure differential, that should be addressed first. But, if there is enough difference, then I need to go after different things like controlling air flow around a specific component, but first things first.

So looking at the table below, I will be hoping to get about 110 mph on the indicator.

MPH	KNOTS	IN. of H2O	#/IN2
30	26.1	.44	.016
40	34.8	.79	.028
50	43.5	1.23	.044
60	52.2	1.77	.064
70	60.9	2.41	.087
80	69.6	3.15	.114
90	78.3	3.99	.144
100	87.0	4.92	.178
110	95.7	5.95	.215
120	104.3	7.09	.2558

I'll report my results later.

One Small Step for Sam - One Giant Leap for Samkind

Finally. Finally. I got it back in the air. I told Sandy that I flew and she said something like "Whew! O-boy". She sounded just like Walter Cronkite.

I didn't pick the date, it just happened, but my third first flight in the Quickie happily fell on the 40th anniversary of the moon landing. Heady stuff for all.

I always told Sandy, "I'll fly it when it's ready". The to-do list finally got whittled down so there was nothing left to do but fly. I haven't posted my recent struggles, like the primary system going dead for no apparent reason (I blew a critical fuse while tinkering) or the back-up system not working (I somehow had discharged the back-up battery down to 5 volts).

But today, all systems were go for launch and I committed aviation. Twice, in fact.

My good buddy C-Rod brought out his entire A&P inspections class witness the crime, in direct opposition to my general secrecy policy for these events. But It worked out - I just ignored them and went into my secret place. You know, where the Olympians go right before that big track or swimming event.

A parachute was offered, but it turned out there just wasn't room, so I didn't wear it.


It started just fine and I ran it up and down an inactive runway a few times and everything seemed strong. With my straightened tailspring and lengthened cowling, I have lost a fair amount of forward visibility while taxiing, but I'll get used to it.


So I went out to 18L and flew. Must have gotten all of three tenths before the oil really started getting hot and I told the tower I wanted back down.

I bounced the landing a bit, but cut me a break, it has been a year and a half since I flew this critter and all's well that ends well.

My residual adrenalin must have stayed with me for a couple of hours. There are lots of things to work on, trim and cooling, etc, etc., but they will sort out in time and I hope to be going fast again.

I have to make a mention here. On the way back from the airport I got a phone call from my good friend Jim Patillo, who was calling to tell me a Quickie builder, Ron Weiss, had been killed while flying another type of homebuilt (Lancair) out in California. I never met Ron but he did post messages often on the Quickie Builders e-mail list, and we sure hate it when we get those calls. I guess you could say it made today's event somewhat bittersweet.

But anyway, after I calmed down a few hours I went out and committed aviation a second time - I wanted to get a better handle on what my new Dynon instrumentation was telling me.

This time, the engine wasn't quite so hot and I was able to stay up for about four tenths of an hour.

That's enough for now, just remember, there is no higher education than aviation. And hey - Let's be safe out there.

There is No Joy in Mudville

Rats!

I thought I had it licked. Last night I was getting roughness in the backup system and also the primary was acting up. This morning I went out early and replaced the electronic ignition spark plugs and the engine ran great in all functions! I have been doing a lot of ground running and I have seen this plug fouling before.

I put the cowling on and called the tower and told them I would like some high speed taxis, then possibly a takeoff. Everything seemed fine until I did my run-up at the end of the runway. The primary system was strong, but when I switched to the backup the engine just sputtered and died.

I ran up and down the runway a few times, then tried it again. Same thing. I tried leaning the back-up system, then richening it. Tried all sorts of throttle settings. No joy, so I taxied back to the hangar with my tail hanging between my legs.

Rats! Did I already say that?

So now, I am officially scratching my entrance in the AirVenture Cup race. We're taking the granddaughters on a little vacation today and maybe I can figure it out when I get back.

I'm dumfluxed. I need an expert to come and help me out.

See you in a week or so.

Sam

Isn't She Lovely?

Not So Fast, Buddy Boy

Or, should I say "It's not ready, till I say it's ready".

The weight & balance is done, and I was glad to see that it came in at 696 pounds, even with all the stuff I added, including extra batteries, heavier paint job, and TWO paint jobs.

I thought I just needed to get the vinyl lettering applied and a few more little items, when go taxi. But, why should it be that easy?

I thought I'd celebrate having the canopy on by running the engine a little. I got it up to 2,400 RPM, then it started getting rough again. What's the deal with that?

Rats.

Maybe that sensor bracket is still vibrating a little. I have a plan for that. Maybe the mixture still needs tweaking. I dunno.

We'll see tomorrow.

Anyway, here's some photos of the mostly complete engine installation.





Mixture look a little rich?

So Close I Can Taste It

I am 90% though my annual condition checklist and the thing is close to being ready.

Yesterday, I hauled it over to AvTech for weight & balance. I had the help of the instructor, Karen and two A&P students, Tom & Colin. I forgot to use my camera, but Colin grabbed these with his cell phone. Thanks folks!


I was happily surprised to see it come in under 700 pounds, 696 pounds, to be exact. I was afraid I would be in the 725 range, so 696 is good, considering all the stuff I've added. We weighed all possible combinations; empty, main tank, header tank, aux tank, pilot installed, etc. I'll figure all the arms & moments later.


Just to remind me that nothing should happen too easily, I intended to taxi the Q-200 over to AvTech for the weigh-in. Unfortunately, there was interference between my air induction tube and the cowling, which resulted in causing the lower cowl to bind against the spinner. So, today I'll have to modify the tube to better fit the cowl, blah, blah, blah.

Happy Anniversary

Today, June 22, 2009, is the 10th anniversary of my one-day trip across the U.S.A. in my Q-200. I guess it doesn't seem like ten years, then again, a lot has transpired since then (the best of which, was marrying Sandy).

Here is the link to the whole story Trip Across USA It's a pretty long read, so I suggest making yourself comfortable and pouring a cup of coffee first.

Here is the radar capture for June 22, 1999 - about mid-day. As you can see I had a bit of a time picking through Oklahoma.


It really is a shame that I can't celebrate properly and go fly today, but alas, I am still trying to hash out engine problems. (I think the engine now has more power than with the old system, I just can't get my back-up fuel injection to work yet). I guess I'll commemorate it by going to the hangar and giving the old girl a pat on the vertical fin.

This little plane has been one of the most rewarding, satisfying, challenging, expensive, hair pulling, bleeding, frustrating, and funnest things that I have ever been involved with.

Here's to my little Quickie!

I Got It ! - I Get By With a Little Help From My Friends

Finally... I know what was causing my woes (besides dain bramage). How long have I been working on this rough engine problem? Two months? Three months? Four?

The problem was finally traced to vibration of the bracket that holds the pickup sensors.

Now, how did I come to that conclusion?

Several of my advisers suggested getting my hands on an oscilloscope (see the previous post). After I sent out the results of that test, two experts said that my problem was the variation in amplitude in the signal - not a phase shift, and was most likely caused by vibration.


I got hold of Don Bartlett (who doesn't like me very much) and he welded a couple of gussets onto the new bracket made by Phil Lankford and Jeff Doddridge, in California.


When I first fired it up, I could tell that things were better, but still not 100%. It ran well on the mag, but not on the electronic ignition, but the fuel injection seemed fine. Fortunately, I had experience with this and figured it was just dirty spark plugs.

I let the thing cool off for an hour, pulled and cleaned the automotive plugs, then stuck them back in.

When I fired it up it ran just great! Wow!!! Did I say great? I really meant fantastic! I brought it up all the way to 2,370 RPM, which I hadn't seen in a long, long time! There was still a slight roughness when running on the electronic ignition, but nothing like before. I think I need some bracing of the sensor bracket, but at least I know what to do!

I want to thank all you guys who were helping me on this frustrating, teeth gnashing, hair pulling episode. I'm going to take a couple of days off for a Hoskins family reunion, but I'll be back at it on Tuesday.

Thanks again, all!

More chasing

Please take a look at these two sorrowful pages of sketches of today's oscilloscope output.

The engine always starts easily and idles very smoothly. Roughness starts around 1,800 RPM. Misfiring is very pronounced, really shakes the engine, and the exhaust is momentarily black.

Page 1.

First wave is pretty much what it looks like with both the 6" and 7 1/2" wheel, at idle. With the 7 1/2" wheel there is a little more of a hump in the middle of the trigger wave. The peak-to-peak amplitude is pretty even and is about 4 volts p-p.

2nd wave. This is what it looks around 2,000 RPM. Notice that the amplitude varies greatly, from about 3 V to 7.5 V p-p. We tried adjusting the air gap from .015 to .060 and didn't see a change here. We thought maybe the variations in amplitude might be from the prop bolts and flange lugs. Just speculation.
3rd wave. Another sketch at high throttle. Here, I tried to include the trigger wave. The trigger wave, at higher RPMs, always had a greater p-p voltage than any other part of the wave, while at idle, the trigger wave was the same.


Page 2.

There always is a consistent phase shift (skipping a tooth?) at any speed. In the sketch, I am attempting to show how it would bounce back and forth. We feel this is a key issue, but have no idea why it is occurring.

We also saw that the amplitude of the wave is pretty even at low RPMs, but at higher revs the amplitude varies a lot. Click on the sketches to better read the voltage ranges.


Other things we tried and noticed:

Changed from 1 1/2" to 6" wheel. no change seen on scope.
Removed the prop bolt closest to the trigger gap. - no change
Tried a smaller diameter sensor. - a little smoother.
Degaussed the crankshaft flange. - no change.
Ran on the single magneto only. - a little smoother.
An automotive timing light flashes consistently at low RPMs, but becomes intermittent, in sync with misfiring, at higher speeds.
Installed the 6" wheel and used the 7-1/2" sensor mount bracket. This caused the sensor to kind of be extended way out from the aluminum bracket. No effect.

I sent these sketches to Tracy Crook, at RWS and he thinks that the change in amplitude is the source of the problem and what I perceived as a "phase shift" is not an issue. Given that, I will be concentrating on eliminating all vibration in the sensor mount bracket.

Sam

Chasing the Noise

I have been corresponding with several of you and thought I'd put a week-end summary into one post. First off, I'd like to thank all of you for your help and patience while I'm going at this problem.

These things had a positive effect:

• Temporarily replacing the 1/2" VRS sensor with an old 3/8" sensor. Ran a little better.
• Centering the sensor over the trigger teeth. Got another 200 RPM and noticeably smoother.
  

These things had no observable effect:

Changing from a 6" trigger wheel to a 7-1/2" trigger wheel (photo attached), and sensor mounting brackets.

• Adjusting air gap from .030" to .055"

These things had a negative effect:

• Swapping the position of the primary and backup VRS sensors

This had an unknown effect:

• "Dressing up" the two tooth gap in the 7 1/2" trigger wheel. Actually, this was a bonehead move. I'm going to attempt repair it by having a pal fill it in with weld, then reduce it, so it pretty well matches the gap on the 6" wheel. The original configuration may help alleviate the phenomenon known as "phantom tooth".
  

This was a positive fix:

• Swapping my standard trigger wheel with Lynn French's aluminum bowl and trigger wheel setup.
  

This is what I know.

• When the engine is set at 6 deg. ATC, the primary sensor is directly over the first tooth in the gap. (photo attached shows the engine set exactly at TDC.).
  
• The air gap remains consistent all around the wheel, within a couple of thousandths.
• The engine starts easily and idles smoothly.
• When at about 700 RPM, the measured timing is around 38 deg. BTDC
• When running at full throttle (2,100 for now) the timing is about 25 deg. BTDC
• At high RPMs, the automotive style timing light flashes quite intermittently at the same time the engine starts missing, indicating, to me, that the signal is getting interference.
  
• Engine now runs pretty will up to about 1,900 - 2,000 RPM

This is next:

• Borrow an oscilloscope to view the VRS sensor signal.
• Repair the trigger wheel.
• Inquire into getting a duplicate bowl, trigger wheel and mounting bracket ala Lynn French.

Again, I invite suggestions and I thank you for the help.

Still Not Right

I am so frustrated. I just can't get the engine to run right. I started with a 6" trigger wheel and after much gnashing of teeth, I borrowed Lynn Frenches setup. I installed his parts, using my sensors, and the engine ran great. That much I know.

I figured my sensors were picking up noise from the rotating prop bolts and I hoped that a larger trigger wheel would help. (Please see the photos in earlier posts). I got a 7-1/2" wheel and had it modified by Phil Lankford and his buddy Jeff.

I didn't want to copy exactly what Lynn did, since he has a V-belt on his prop hub to drive an alternator. My alternator is on the pad on the accessory case.

Here's a couple pf photos of Phil & Jeff's parts.



I do have a couple of smaller diameter, and very used, electromotive sensors and I'll try rigging them up tomorrow, just to see if that makes any difference.

This sucks. Any comments, please?

Plane Progress - Slowed to a Crawl

Okay, Sam... What's the latest? Are you close to flying again?

Well, I am closer than before. Phil Lankford, in the San Diego area is working hard to get me a new trigger wheel and mounting bracket worked up. That should show up within a couple of days.

The new Bob Archer com antenna is installed, as is the remote compass for the Dynon D180.




Since I have gotten my system back-up battery installed, I should be able to permanently install the tail cone today or tomorrow.

My back-up fuel injection system is still buggy, but I have to get the engine running again before I can try that out.

So yes, I am getting close. When I get all the pieces back on and working I'll go through my entire Annual Condition Inspection checklist and make sure that I haven't left anything out.

One Reason Why Progress Has Slowed Down

On May 8th, a huge storm blew through southern Illinois. It wasn't just a thunderstorm, it wasn't an inland hurricane, it wasn't a tornado. It was a derecho, a term I don't recall hearing before. Read about it here: http://en.wikipedia.org/wiki/Derecho


I drove through the first wave as I left Murphysboro. I was half way to an airshow in Branson when Sandy called and told me they were getting blasted by the second wave, which the local weather guy called "the head of the comma". There were sustained winds of 90 mph and gusts over 100 mph.


Here is a technical description of the storm. Scroll down to May 10. http://www.weather.com/blog/weather/?from=blogredirect%3f


Here are a bunch of photos showing the impact. http://www.flickr.com/photos/thesouthern sets/72157618012419861/show/

We were without power for 6 days. Well technically, Sandy was without power for 6 days. I only was unconvinced for three nights because the first four I was staying in the Hilton in Branson.

Thousands of trees down, perhaps 2,000 utility poles broken and hundreds of utility workers from as far as Florida and Pennsylvania came in to clean up the mess.

We lucked out. Just a little damage to the gutter on the garage and a few tree limbs.

The big question is; How can we live in southern Illinois without a basement or storm shelter? How crazy is that?

Our house sits in what was the path of the 1925 Tri State Tornado, the worst tornado the nation has ever seen. http://en.wikipedia.org/wiki/Tri-State_Tornado Take a look at the photo of Longfellow School on the Wikipedia page. They never rebuilt the school but converted the land. Longfellow Park is about three blocks from our home.

While there was damage to some buildings at the Southern Illinois Airport, MDH, the T-hangars and the planes within them were unscathed.

I Finally Figured It Out

That's what my dad always used to say, "I finally figured it out". He was always talking about the meaning of life. In my case, I just want to figure out how to make the damn engine run.

Thanks to Lynn French, I definitely know the ignition problem is due to my trigger wheel and sensor assembly. Lynn was kind enough to lend me his parts, while his engine is down, and I bolted it on this afternoon. Lynn has the 7" trigger wheel, while I have the 6". I used my existing sensor and wiring.

The engine fired up just fine, as always. After it warmed up I ran it all the way to 2,320 RPM. I haven't seen the engine turn that fast and smooth in a year and a half. While I was at WOT I switched off the mag and the engine didn't miss a beat.

Here are some photos of Lynn's trigger assembly mounted on my plane. Compare them with my installation in my previous post, dated April 19.


So, without a doubt, the smaller wheel must be causing me to pick up noise from the crank flange and prop bolts.

That's the good news.

Now, I have to figure out what to do about it. My first inclination is to see if I can find a different sensor and use the existing wheel. I have a lot of $$$ in that trigger wheel, and looking at Lynn's parts, I'm sure he even has far more machining than mine. I know a rep for an industrial sensor company and I'll give him a call tomorrow.

Maybe I could use an aluminum plate, with the embedded magnets, like Klaus uses. I would have to know if that type of Hall Effect device would work with the EC3.



Any other ideas?

Figuring out the Electronic Ignition

Gee, no posts for a month. You'd think I wasn't doing anything. Actually, I've been stymied by the engine. The general symptom has been that I can't get full RPM. Before I started this conversion, I was getting 2,300 static RPM - now I can only get around 2,100, and it's rough.

Yesterday, I finally narrowed it down. The problem is definitely with my electronic ignition, and most likely my installation portion of it.

Yesterday, I ran the engine again, but this time I hooked up an automotive timing light to the #1 spark plug lead and kept the light in the cockpit to closely watch the flash and see what it was telling me. At low RPMs, idle through about 1,500, the flashes were nice and steady - just like when I did the Mode 8 check with the engine off.

However, as I started to raise the throttle, the flashes became intermittent.? It's as plain as day and I don't' know why it took me this long to see it. The faster the engine ran, the worse it got.

When I retarded the throttle, as I came back down to the 1,500 range the flashes on the timing light became nice and smooth again. So, now all I have to figure out, is why this is happening.

I still think there may be trouble in my 6" trigger wheel/sensor installation - possibly picking up noise from the crankshaft flange and prop bolt lugs. Lynn French's engine is down right now and he is kindly lending me his 7" trigger wheel and mount, and they should be here soon. Swapping those parts should quickly confirm or disprove that installation issue.

Air Intake mods - More Sawsall Art

I continue to plug away at programming the EC3 and things are getting better. The mixture plot is getting smoother and the engine is running better.


I have a fifth fuel injector, which is used as a back-up, but it barely ran. I found that it was over-sized, capable of delivering 87 lbs. of fuel/hour and the mixture was extremely rich. This seems to be out of the adjustment range of the EC3 so I ordered a 55 lb./hr. injector. It will be here next week, so in the meantime I am holding off on tuning the engine and will tend to a few other items on the list.

All along, I have been planning a radical change to my combustion air intake. This was successfully accomplished by Harry Hinckley and Greg Zimmerman in Greg's FAST Swearingen SX300. There will be a little scoop in each plenum snout. This air will be directed, through two hard tubes, to the throttle body. Here is a photo of the mock-up I made last year. I have since made the pipes, now I just need to get the scoops placed in the plenum.


As usual, I start with pouring in 2-part foam, held in place with paper dams & tape.


Then I get out my favorite shop tool; Mr. Sawsall:

I use the 14" saw blade to gently remove some of the foam I didn't want.

After rough trimming, I attached a couple of pieces of hard foam, using 2-part foam as glue. The hard foam will make a better foundation for the lip of the scoop. Some wire pins hold the hard foam in place while the 2-part expands.

Since it's cool in the hangar, I'll wait a day before I get into the detail carving.

This may all seem hare-brained, but what the heck. That's what experimental aviation is all about.

More forwards and backwards

The closer I get to the goal, the farther away it gets - at least, sometimes it seems that way.

My current challenge is getting the electronic timing correct, then to program in the mixture "map". To map the mixture settings with the RWS EC3 Electronic Control Unit (ECU), you will input a setting for each 1/2" step of manifold pressure; from idle, all the way to full throttle. You use the fuel/air gauge to determine what the mixture is, at that throttle setting.

This ultimately provides a look-up table for the ECU for any given throttle input.

Before I do that mapping process, I need to get the base ignition timing right. This consists of making a sole timing setting, the "base" timing. In my case, since I am using 9:1 pistons, it will be 25 degrees BTDC, with the engine at full throttle. By simply pushing a button, you use the ECU programming panel to advance or retard the timing.

So that's the theory. The reality of it all becomes more difficult, at least, for me.

First thing is the working conditions. While southern Illinois is hardly the coldest place in the nation, I am getting tired of winter.

I first tie the tail down to a front wheel of my car to keep it from going anywhere. In order to perform the timing, I have to beg a volunteer to come out and run the throttle for me.

In the above photo, (click to see it bigger) you can just see the toothed timing wheel, just aft of the propeller spinner flange. I mark some of the teeth for timing reference. Then I have to hook up a timing light and have the volunteer run it up to full throttle. I lean over the engine and hold the timing light within two inches of the spinning buzz saw. Since it's pretty bright outside I even have to shade the timing marks with my other hand so I can see the strobe flash. I actually kind of rest the side of my hand on the aft end of the spinning prop extension. I'm not sure that OSHA would approve.

I have to wear two jackets, goggles, hearing muffs and a hoodie to keep myself together. I calculated that at 35 degrees and 100 mph of prop blast, the windchill is 14 degrees. But that is really only half the fun. The other, is the sensory kick I get from the combination of the prop blast, the major engine vibration and noise, the snot blowing out of my nose fogging the goggles, and the inherent danger of working around those spinning parts.

So, after repeatedly (10 times?) doing all that, we found a few discrepancies. One, I made the sensor mounting bracket wrong and will have to re-do it. Two, for some unknown reason the engine runs worse when the timing is in the right place. Three, my digital tach bounces around so much I'm not really sure what it is telling me.

So whine, bitch and groan.

But, at least I keep working on it, and I guess that's progress.

Thanks, today, to John Eynon for patiently running the throttle for me.

Closer to the Goal

The recent effort has been directed towards getting the engine to run properly, with the RWS EC3 system. There are all sorts of variables to work through; new throttle body, injectors, homemade induction pipes, the list is long.

Right now, I'm working through getting the mixture and ignition timing properly adjusted. This is a pretty big deal and will take a while.

To complicate things, the readings from the mixture meter have been unreliable. Here is the one I'm using.

It turns out, I mounted the sensor too close to the end of the exhaust pipe. The O2 sensor is very sensitive and I guess that ambient air is getting sucked back into the exhaust pipe, between pulses, particularly at lower RPMs. This winds up showing the mixture to be too lean. As suggested, I clamped on a piece of pipe I had laying around and the mixture meter reading instantly got better.


Again, the use of this meter and sensor is only temporary, until I get everything calibrated.

Right now, I'm running the engine without the canopy installed, which is giving me a real wind-blown hairstyle. The best I have seen, at full throttle is about 2,200 RPM and 29" hg. I have old data that I had attained 2,340 RPM and 29", so I have little way to go.

I'm getting some of the wiring tidied up and pretty soon it will be time to, hook up the rudder cables, install the back-up battery and install the canopy.

On another successful note, my custom designed and built fuel flow circuit board works just great. The Dynon D180 allows you to connect a flow transducer. These transducers typically have a little fan in it, that rotates as fuel flows. A sensor picks up the pulse count and sends it to the D180 and indicates flow in gph. The problem with my system is that fuel passes through an open loop, starting at the header tank, running through pumps and filters, past the fuel injectors, and then back to the header tank. Because of this, any fuel flow transducer will sense ALL the fuel flowing and not just the fuel consumed.

Note: the flow out of the injectors is controlled by the duration of time that the injectors open. More fuel demand - the injector pulse width increases. Less demand - narrower pulse width. The number of pulses per engine revoultion is fixed.

Mike Dwyer to the rescue. Mike is a Dynon dealer and an electronics whiz. Mike designed a circuit that takes a signal from an injector. It converts an increase in pulse width to an increase in pulse frequency. It's all black magic, to me.
I got with Dennis Hannon, the avionics instructor at SIU, and an avionics student, and they fabricated and bench-tested the converter. I named the piece the Dwyer-Hannon Frequency Converter.
And what do you know? I works! Fantastic!


Mike designed in a calibration potentiometer, but the Dynon also has an adjustment multiplier. There is a little formula to dial in the calibration, so in a short while my fuel flow indicator will be correct.

Sweet!