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electronic controls for air cooled old aircraft engines


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whew, that wasa a mouthfull, thanks large and no4

 

I just have become "open minded" in looking at my engine. I always planned on having a lot of work to install an engine, i was just sure it would be a continental diesel!!!

 

Now it is not, it is a continental gaser.

 

I'm just taking a fresh look at it. I already have to build a new exhaust system for the engine, as one for the cozy is not available.

 

So, after meny posts on this forum i have come to learn about turboes and that the duty cycle on an airplane is actually easier than an automobile, less starting and stopping.

 

I always planned to use electronic ignition, it was going to be lightspeeds, now it may or may not be lightspeeds.

 

People have said that turboed engines are "hanger queens", I am trying to figure out why and correct the problem.

 

I want power to a higher altitude than the original engine is rated to (25000 vrs 18000) at the rated boost of 31.5.

 

I found out that continental tried timed fuel enjection in the ancient past and the engine ran great and really smooth, they just couldn't start the dam thing, he he he.

 

Cost is a factor and it is not a factor, i originally planned on 35-40 thousand for a new cont diesel. I have now spent 7000 on a used cont gasser and if i can make the changes for 5 to 7 grand, it will be cool, i will still be under budget.

 

I am looking and learning and will be putting wrench to engine weekly starting in about a month.

 

My goals are.

 

make a lighter, more powerful turbo system

 

interlool to help stop detonation

 

electronic ignition to vary timing for better, smoother running

 

electronic fuel metering, set up when probes are new and reliable for more even egt per cylender, allowing lean of peak in cruise for increased fuel economy and range.

 

These are my goals, but, i can asure you i don't know which i will achieve, only time will tell and i will tell of the sucesses and falures.

 

enjoy the build

 

Mike

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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Mike,

Two grand for your 6-cyl Cont is a killer price. On the surface. You might want to examine the notion that that's a red herring. Like it's still $15k to overhaul (if it makes it to TBO - which it probably won't) and in the interim, valves are still a cuple of hundred $ and stuff like that. Then, even if you use Tracy's EC2 you have turbo and all the heat rejection problems. Engineering that only costs you time, but heat rejection could get pretty serious and time consuming. Turbo itself will probably be another matter. ANY turbo is expensive. Going with stuff like automatic wastegate control will almost certainly be expensive and not buy you a whole lot of reliability. I'm not sure about aftermarket turbos, but a guy I know (on the Soob list) has been turbocharging all kinds of stuff for 25 years or so, and is really good and really creative.

 

Anyway, if it was me, I'd be inclined to talk to Turbo Tom about aftermarket setup for the most cost effective (manual wastegate, etc) setup and learn to monitor the engine myself to avoid overboost (not a difficult thing to get used to). I'd fly the airplane for a while, iron out the kinks and demonstrate that it works well. By that time, John Slade will have done all the heavy lifting on his turbo rotary and you will be in a position to replicate his work for "pocket change" after selling your Turbo Cont for a tidy profit to some poor benighted soul who is "autophobic". Make money on the $15k-to-overhaul monstrosity before it needs to be overhauled, and go with what you can support with walking around money.

 

You got a really killer price on the engine, but the maintenance is apt to kick your ass ... Jim S.

...Destiny's Plaything...

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The engine is gaurenteed for a year after i start flying, when overhaul time comes, i'll just do it, it isn't hard and it will cost 8 to 14 grand.

 

As far as heat is concerned, i know i have to worry about both radiant and ???(forgot the word) heat and will well shield and have extra airflow for both.

 

Jim, do your rotory thing, i'm not and continual answers to my use of a continental or lycoming is silly.

 

enjoy the build

 

Mike

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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Dust,

Regarding the turbo problem, I've been told that you have to plan your descents very well to prevent cooling problems. The engine will run hot, with a lot of heat trapped in the turbo and exhaust manifold.

If you suddenly cut from 75% (less than 31", more like 27" I guess) power at 15,000 feet travelling at over 200 mph, the front cylinders will freeze, whilst the rear ones will cook.

Bang bang hello trees.

I'm told the trick is cowl flaps open at the end of the cruise to commence cooling, cowl flaps closed and a slow reduction in power and speed to commence the descent, and then a smooth trip down . As you approach the circuit you have to warm the engine back up, otherwise full power in the go around might be catastrophic.

The Cozy is pretty slippery! So it might take some thinking out.

 

Very excited down here in NZ to find out how the beast will go when she is ready.

 

Have you got yourself a pressure suit? Don't want to get the bends up there at Fl 250. I was reading about a guy in a small GA turbo plane forget which) who was up at 30,000 feet. All the Airline Captains passing were saying " What the hell are you doing up here!".

The Coconut King

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DUST! No wonder I haven't seen you lately... you've been hiding out over here in the engine discussion area. And I see you are making new friends! :P

 

I'll throw in my 2 cents and maybe take a little heat off of you!

 

Continental: don't listen to the ridicule, stick with what your comfortable with. Some of us are going for new technology. That's their choice, that's a choice I'll probably be making as well. But for all the talk about reducing failure points by eliminating valves and cam shafts, we introduce new mechanical failure points with water cooling and PSRU's. To borrow a phrase from No. 4, glug glug glug hicup fart bang hello trees. We all weigh what we get, what we loose, and we place our bets on the horsepower of our choice. One thing that can't be disputed (although I'm sure someone will try) is that the Continental has many proven reliable hours in the design... that's how you get to be old.

 

TURBO: What is the compression ratio of the engine? Most of my experience has been with automotive engines (another reason I'm leaning toward an auto conversion) but the principle should be the same. Above 9.0 to 1 and you could have tuning problems (lookup "Hanger Queen"). I've had an engine with 10.7 to 1 with a big honkin turbo, so it is possible but it can be cantankerous. Below this and an engine can swallow the extra air fairly easily without throwing up...

 

Intercooling: Must have item. Easiest way to squeeze more efficiency and reliability out of a turbo engine.

 

EFI/ETI: I too suspect Tracy knows what he is doing. What hasn't been mentioned about mapping is that it is usually not 2 dimensional. The computer doesn't just read RPM to decide how to go squirt bang... most computers now read other variables like OAT, EGT, boost, load, et al. (And that's just the computer in my wife's oven!) Even if some of these inputs are removed (like real time EGT), the original mapping is based on these inputs. Tracy can tell you what inputs the computer needs to derive the information it needs to use the proper outputs.

 

Shock Cooling: This is a problem you'll have to live with no matter what you do to a Continental (or Lycoming).

 

Overhaul $: well... you didn't really ask that question, did you? :D

This ain't rocket surgery!

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That's the darndest thing about reliability: You never know that it is - until it is! Then it was the whole time until you found out it was. Then everyone will try to prove it wasn't because of what they read or heard or happened to them once.

Does that make sense?

Well, fuel injection and turbo-charging/normalizing has come a long way in the last 10 years in the Lyc / Cont realm. If you can afford the newest in air-cooled technology, you'll probably not be posting questions here, discussing prudent investments in wind-power. But, like most of us here and perhaps those who wrote some FAA rules awhile back that gave permission to those who would experiment: There maybe a different way to do things that may be cheaper or better, but as long as it's safe, we're all for it!

I've flown many hours in "spam cans" and have seen and lived the foibles of "simple" "KISS" turbo and FI systems. When they work, they work. When they don't, they don't. If you live through a failure and your aircraft survives, a realist will always wonder if the same equipment will fail the same way if replaced.

I, for one, deal with technical advancements in industrial machine control technology where failures can be very expensive in many ways. Simple works. But it is limited. When you bring technology to the next century, sometimes you use the same wagon, but it is better and more reliable than the old one. It is because of design, we make it that way. Is it compatible with old technology? Well, piston engines are still driving new cars around aren't they?

As long as the laws of nature tell us that things shrink when they cool off, we will always have the limitations of air-cooled technology if we decide to use it.

Benefitting from experimentation is how we got this far. I refuse to believe we have not improved on the basic design and operation of the internal combustion engine. Manufacturers of such engines have to be able to show a fiduciary purpose (and convince the FAA under part 21 and others)to be able to make changes to such engines. The costs of such change may not make enough profit.

That leaves it to people like us.

So, take notes and be careful. Keep current and don't let your physical go.

Contintental power is my second choice (TSIO-470) because of availability. I am interested to see how it turns out.

 

Kevin

(Sort of a "motor head" rebuilt 292 Ford V8 at 11 with my older brother 13 in 1967)

Back to building... #618 Cozy MK IV

 

My Cozy web pages, courtesy: Rick Maddy... :cool: WN9G :rolleyes:

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These are the additudes i am looking for, conservative, but willing to look to the future. I am lucky because one of my friends is a retired automotive engine engineer and when i mention the things i am planning on, if he thinks it is doable he says so, if it is questionable, well, he says that too.

 

I, of course, want realiable, i'm not even against two of everything, time will tell, i'm just at the very very beginning of defining my goals and opening up to the idea of doing this at all.

 

The point on shock cooling or what ever you want to call it is well taken and i am thankful for it as the engine manual says the same thing and it made me think of bypass cooling for the cylender heads, will see.

 

the plan for now is to gingerly give up altitude as i decend, 2-3 hundred feet per minuit, i paid for it on the way up, no sence in giving it all away.

 

And it will be a Loooooooooooong cross country with good winds that will take me to 25000, just want to be able to, if the conditions warrant it.

 

Did learn an interesting thing, the factory runs all new engines on the ground for three hours with a "club" and no additional cooling, so, i will probably make one, my hobby is woodworking and fabbing a "club" for ground running to test systems and parts will be a good thing.

 

I thing thier is probably a good reason for using a club instead of a prop. Anyone know what it is?

 

Wouldn't mind a 100 mph tail wind, wouldn't want a 100 mph headwind!!!

 

enjouy the build

 

Mike

maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

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Well Dust if you fit the prop on, and give it the whoomer (that's full power to you), you've got a firebreathing 220 hp monster trying to rip the test bed off it's moorings, if not properly secured she'll be through the hanger wall and ploughing across the apron with people running for cover! Or if you do manage to secure it well enough, you'll have a mini cyclone blowing @#$% all over the place.

 

The clubs are fat and heavy, and the shape of it produces neutral thrust, just lots of drag, which absorbs all the horsepower.

:D

The Coconut King

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There's not a lot I've seen on the net about turbonormalised aero engines, but I did find this.

 

Turbonormalisation

http://www.nar-associates.com/technical-flying/turbo/turbo.pdf

 

The main site with lots of fascinating stuff

http://www.nar-associates.com/technical-flying/technical_flying.html

 

It refers to the Bonanza, but is appropriate for Dust's engine, you turbo rotary guys and hopefuly some day soon my Cozy uber diesel as well.

:D

The Coconut King

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