Autosport Labs

Agreed, disregard my comments about radial aircraft (not rotary) engines. Bruce Roe

I may be entirely off track here, thinking of a radial engine. A 3 cylinder engine will have firing intervals at multiples of 120 degrees,
won't it? Then you may have a possibiity. Just what it the firing interval, will the engine work with waste fire? Bruce Roe

Even with dual plugs per cylinder, you can't use the same coil to fire them. An EDIS coil drives 2 plugs which reach TDC at the same time. But the expectation is that one is a compression stroke needing a lot of spark energy, and the other is an exhaust stroke needing minimal energy. 2 plugs on the ...

The MJLJ-EDIS can operate engines with a 90, 120, or 180 degrees crank rotation between power strokes, or multiples of these. That doesn't usually work on a radial with an odd number of cylinders. If you don't have 2 cylinders reaching TDC at the same time, it would take twice as many coils. Bruce Roe

The usual way to use a TPS, is apply +5V and ground to your pins 1 & 4. Then sense voltage out to the MJ from 2 or 3. Th MJ can supply the +5V. Exact resistance not important. Bruce Roe

If its not a straight 4, what is the configuration? On my 2 cyl I used a V8 EDIS, because the 90 degree angle between cylinders was the same as a V8. Bruce Roe

Go to the OPERATION section, BATTERY CURRENT FOR EDIS April 2010. The EDIS uses electronic dwell control, so it only takes the current needed to charge the coil(s) each revolution. Current increases with rpm, of course. Much more efficient than a points system, that burns up extra power in a ballast...

Funky Diver recommends a good test, because it will find shorted turns or breaking down insulation that won't show up with an ohm meter. If a couple plugs don't spark, switch the EDIS coil driver wires. If the same plugs don't spark, its the coil. If different plugs, its the EDIS driver output. Bruc...

If you can get reliable & repeatable output, a reduced rotation TPS would work. Either calibrate the controller for a lower range of voltages, or use an OP AMP to boost voltage back up to nominal levels. Bruce Roe

Can't see the trigger wheel setup, is this a factory thing? The phasing appears OK, the "double hole" is where the missing tooth is? The wiring checks, reasonable VR gap with wires shielded & not reversed? I'd take the plugs out but wires still connected, wire the bases to ground. Unpl...

Great work, nice pictures. Did you remove one tooth from the trigger wheel before installing the engine? Bruce Roe

Do you have a 36 - 1 tooth trigger wheel pattern for the VR? The only thing visible in the picture is starter gear teeth. Bruce Roe

Are you running an EDIS4? Can you show a picture of the relation of the VR to the trigger wheel when cylinder 1 is at TDC? Bruce Roe

If running a single cylinder on a dual output coil, the other output of the coil must be grounded to complete the plug circuit. Bruce Roe

A MAP is better if your setup can use it. The engine torque is pretty much proportional to Manifold Absolute Pressure. But Throttle Position has a very poor relation to torque. First the restriction isn't a linear relation. Then, it only takes a little throttle for max torque at low rpm, but max thr...