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Turn Your Secondary Ignition Into a Fully Programable System

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Schmleff

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This is pretty cool. CB performance makes a "Black Box" that allows the user full control over their ignition advance. At $200 bucks, it would be a worthy investment.

Link: CB Performance Black Box Ignition System

The software looks the same as what I am running on my digital secondary. Had this been available when I was putting the new FWF package together, I would have used this with a low height secondary and saved hours of design and fabrication.

Why mess with it? Lots of reasons. Starting, smoothness, fuel savings and of course power.

From what I have read from many sources, a properly advanced ignition can save quite a bit of fuel. I have heard the Lycoming guys say that they are burning between 1-2gph less in cruise. Not sure if that number directly translates, but it they burn 10gph in cruise and we burn 5, I think its save to say that you could save at least .5gph in cruise.

If you are interested in it but are not sure about the programing, I would be happy to put together a few curves and help anyone through the setup.

As usual, you are buying it for an "off road vehicle". No, I don't get a spiff for pitching CB. I am blacklisted from their sales system because I own a scary airplane.
 

Pops

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I am very interested. I fly a little single seat Super Cub, ( really its a Fisher Super Koala construction but built to the dimensions of the Fisher Koala 202). EW is 450 lbs, engine is a 1835 cc, 60 HP, 1200-1300 ROC, cruise at 80 mph at 2650-2700 rpm. At this time, I have single ignition with a slick mag driven off the crank with Great Plains mag drive. No electrics, starter at this time. I have a firewall forward weight of 141 lbs and want to same every pound that I can. Wanting to go to dual ignition in one way or another. Not so much interested in more power, I could go for more cc's for that, but wanting long range. I'm putting on a new set of wings with larger wing tanks for a total of 16 gallon. If I could get dual ignition and a bonus of .5 gal or so less fuel burn, Great. Also, I use a little 12v, 5 amp battery for my handheld radio, oil temp gauge and electric elevator trim. Keep it charged with a solar. So, I'm wanting the reliability of dual ignition and a lower fuel burn with adding a minimum of weight.

Dan
 

djschwartz

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Portland, Oregon
Switching to an electronic ignition with variable timing won't do much of anything for maximum power at sea level unless the original mag(s) were mistimed or weak. But it will definitely help fuel consumption at cruise, especially at economy cruise settings of 65% or less. It will also help power at high density altitudes where the engine is really only putting out cruise power or less even with the throttle wide open. Those are the conditions where the timing should be advanced from the WOT, full power at sea level, setting for best operation.

There was another thread on this subject a while back. For that thread I researched and posted some BSFC numbers related to this subject.

Dave
 

Schmleff

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Waupaca, WI / USA
Dave,

Thanks for the feedback! I brought up power relative to the maximum retard of a typical impulse coupling 28 degrees.

I was limited to 30 degrees of total advance with my single Slick mag. With the mag set at 30 degrees, the impulse coupling fired at 2 degrees before TDC which made hand propping exciting ; ) With the digital ignition (I have the crank fired version installed) I can change the timing when conditions would permit, such as cooler seasons.

CB's entire crank fired system is still cheaper than a mag at $570. I had to design a 36-1 tooth wheel that fit on the prop hub and a bracket for the VR sensor, but other than that installation was pretty simple. Installation of the Black Box should be even more straight forward.

Here is what I am using for an initial curve (ignore the strange numbers in the middle, that has been fixed):

Timing Table.jpg
 

dcstrng

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Okay, this is seriously intriguing; if it is as straightforward as it looks…

Am I missing something – looks like, lock the mechanical advance, install the CB unit (not real clear what that entails), drag out the computer to map the thing and fire it up… digital things scare the heck outa me (don’t like machines that are smarter than I am…), but this seems fairly undemanding…

I'm doubtlessly missing something…:ermm:
 

Pops

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Some VW type 1 engines have a total advance of 32-35 degrees. The 1969 that I bought new was listed at 32 degs.
I am running my 1835 cc, Type 1 VW engine with a mild 7.5 to 1 CR at 28 degs with a Slick mag. Burning 100 av fuel, it could be advanced more, but like Jeff said, can't do it with the Slick mag. I hand prop only. Dan
 

Schmleff

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If its anything like the crank fired one I have, its pretty easy. Coming up what an aviation ignition map might look like took weeks of study...
 

Toobuilder

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Switching to an electronic ignition with variable timing won't do much of anything for maximum power at sea level unless the original mag(s) were mistimed or weak...
True, the gains in max power are not significant, but we need to remember that locked magneto timing is a compromise between cruise AND takeoff performance. But there is no doubt that variable timing is very good for fuel economy. Heck, I'd think a good old Bosch 009 ignition with the appropriate curve would outperform the magnetos used on the aircraft conversions.

...And once again, gain, the CAFE foundation has an extensive study on aircraft electronic ignitions.
 

Pops

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Bosh made over a hundred different distributors in the life of the VW engine. The 009 is not a cure-all for every VW Type 1 engine. Has the wrong advance curve for the latest carb on the type 1 engine. The engine will have a stumble a little off of idle.
Dan
 
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PTAirco

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My friend David Mickleburgh made an electronic ignition package for VWs with a built in tailored advance curve suitable fro handpropped engines. After breaking his thumb on a backfire, I should add! David is no longer with us, but his website and business was looked after by his son for a while. The site is still up and if you're looking for a proven system, it might be worth contacting him.

leburg.com - Leburg Electronic Ignition for Light Aircraft

 

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