Thorp Air Command - T18.net

Dan,
That's true. The basic EDIS module has the limp home mode, if the advance info from the computer is corrupted. It also works if no computer is connected at all.
The cheesy video shows the EDIS system running without computer input. It's running in limp home mode.
I intend to replace one magneto with this system. It's so simple, reliable, and inexpensive.
In limp home mode, the EDIS starts firing the coil pack with no advance, then advances 10 degrees above 400 RPM. If I installed it 15 degrees advanced, then above 400 RPM it would be timed just like a mag, at 25 degrees.
The other mag is a Pmag, which will do all the starting chores. Starting after TDC, advancing with RPM and manifold pressure input.
The aftermarket control for the EIS system is the MegaJolt E. It's not required for what I have in mind, but for $162, it adds full programmable control of advance with RPM and manifold pressure input, similar the Pmag, EFII, Electroair, LightSpeed, etc.
The challenge is making it fit up to the Lycoming in a reliable, simple, inexpensive way, then test it.

_________________
Scott Emery
EAA Chapter 326
T-18 N18TE

2330 HRS, the old 320 just got its oil analysis back, the analysis was normal. I keep thinkin the old bugger Will start givin it up, it's been together since 1968 and never had a top end. Who else has a high timer. Dan

My 1984 Volvo with 420,000 miles had the "limp home" mode built into the distributor/computer . Same electronic ignition for 28 years with no failures ! BOOM ! Not exactly sure what the lump home mode would provide , but I assume low RPM/engine performance just to get it off the road for a tow ?


RB

I will bet your plane will still be flying in the year 3000 also Rich, especially the way you keep that rig. Spotless!! Dan

I installed the Pmag in 'Fiesty' over the week end. It flew great, and seems to have about 60 RPM more at top speed. The air was a bit rough, so I couldn't determine Feisty's top speed, but with more RPM, it must be faster. with variable advance, it also idles slower and runs smoother at low rpm. Even more if I shut off the Bendix mag.
Feisty did give me a little drama. After the initial engine run, while I was taxiing out to the runway, the right brake dragged me into a 3 MPH ground loop.
Soooo, I disassembled the brakes and cleaned everything, then it was fine. When flying off grass strips, more brake maintenance is required, plus T-18's brakes are very close to the ground.
Anyway, the Pmag is not quite as easy to install as they advertise, seems like I had to at least slightly modify everything. They do not come with hold down clamps, so I had to make some. The plug wires are too big to fit the air box bulkhead seals, so I had to drill them out. Additionally, the plug wires are not supposed to be bundled together like the wires from a magneto they need to be kept apart, so re-routing and separating. The Pmag needs ships' power, so I had to drag a wire thru the firewall and tap some power from the ignition circuit, plus add a power switch for the Pmag.
With a T-18, we all know there is very little room to dive under the panel and get both hands to the fire wall. I have cuts & bruises to prove I made it all the way in. I'm a slow worker, but two days later I was flying.

_________________
Scott Emery
EAA Chapter 326
T-18 N18TE

The VANSairforce community has a forum thread going about the Ford EDIS magneto replacement.
http://www.vansairforce.com/community/s ... p?t=135476
I was pretty excited about the flywheel mounted timing wheel until I check 'Feisty's' flywheel. It's the smaller diameter pulley for the alternator belt, so there is not enough room inside the pulley to mount a timing wheel or magnetic pickup.
However, Dan Horton built a Magneto Hole mounted timing pickup and has been flying with one EDIS + Mega Jolt ignition, with one magneto.
That forum thread has been read over 10,000 times, and is getting some good posts. Dan H posted a pic of Electroair's mag hole timing pickup.
http://www.electroair.net/experimental_ ... _kits.html
I ordered one this morning, to be adapted to my collection of EDIS components.
This is a long journey since my first magneto problems, but 'Feisy's' remaining mag is finally about to be replaced with a worthwhile upgrade.

_________________
Scott Emery
EAA Chapter 326
T-18 N18TE