FS: trigger wheel system for type 4, Megasquirt, $120 shipped Options

[jarred]

Designed these for my 914 and bus megasquirt projects but built a batch of 10 while I was at it in case anyone else found them useful. Specifics...

This is a 24-2 trigger wheel and sensor that mounts inside a Bosch distributor (009, 035, 050, etc) and uses a Hall effect pickup to generate a trigger signal for coil on plug or wasted spark ignition systems. Installs in 5 minutes and is much more discrete than all of those on crank 36-1 VR based systems with the brackets, etc. Tested on VW/Porsche type 4, VW type 1, and Porsche 356 and 912 engines, but will fit a broad range of Bosch 4 cylinder distributors. Can parallel two wasted spark coil packs for twin plug applications. I recommend the VW 2.0 coil pack VAG part 032905106B/032905106E which fires with logic level signals rather than requiring ignitors.

Uses the Allegro 617 hall effect sensor. This sensor is internally pulled up to the power supply with a 10k resistor, so if you need a 5 volt square wave output (logic level) then power it with five volts. Need 12V? Power it with 12 Volts.

3 wires, power ground and signal all in a shielded cable ~5 feet in length.

Wheel is a 24-2 which looks like a 12-1 on the crank. Will work with most Megasquirts but please do your research.

I currently have 10 in stock and ready to ship.

[jarred]

Bfrymire: Yes, I suspect it'll fit a lot of Bosch 4 cylinder applications. Bosch was remarkably consistent in the geometry of their distributors. So likely add to that list Saab, Volvo, Alfa, VW etc. A lot of L-jet and CIS cars used an ignitor in place of the points with spark still running through a cap, so they're kinda halfway systems that many don't bother to upgrade to full distributorless ignition.

Pilothyer: If you only want to eliminate points, you can use the Pertronix system which replaces points with a hall effect sensor and ignitor, advance is then still handled by the distributor. I recommend getting the 2nd generation that doesn't burn out if you leave the ignition on while the motor is not running (like listening to the radio with motor off).

My system provides the reference trigger signal to a fuel injection and ignition controller. The stock 914 fuel injection does not control ignition, it uses the firing signal on every cylinder to batch fire the injectors, the rest is handled by a classic points/cap/rotor system with advance dictated by springs, weights and the vacuum pot. The megasquirt (as an example of an aftermarket ECU) can control various types of ignition systems and fuel injection (batch or sequential). For injection the aftermarket ECU just needs a firing signal like the stock would, but for ignition it needs to know the position of the crank (for wasted spark) and/or the position of the cam (for coil on plug). Wasted spark is the easiest way to go. Just to do ignition you could use a Megajolt controller, but for the price and effort you might as well get a megasquirt and give yourself the possibility to upgrade to injection control later. I normally recommend doing one or the other first, get it running, then move to full FI + ignition control. A megasquirt 1 running MSexrtra code ECU is around $200 from DIY Autotune and works perfect in our machines. The fancier versions add control for modern thing like drive by wire, sequential injection (primarily used for fuel economy), various sensors and controls our cars do not have (stepper air idle control for example). Anyone interested in more info please feel free to ask.

Jarred

[Bob L.]

Pilothyer: If you only want to eliminate points, you can use the Pertronix system which replaces points with a hall effect sensor and ignitor, advance is then still handled by the distributor. I recommend getting the 2nd generation that doesn't burn out if you leave the ignition on while the motor is not running (like listening to the radio with motor off).
Jarred
[/quote]


I believe Pilothyer is referring to the "fuel injection points" not the ignition points. They tell the fuel injectors when to squirt as opposed to firing the spark plugs.