Megajolt Ignition Controller Questions

That is what I have done to mine. If you want, Pm me and I will give you all the detail of what I have done. It works.

 

John,

it's not that complicated but you have to manufacture some custom parts:

• A 36-1 trigger wheel for installation on the crank shaft damper. A good start is to source a 5.125" universal trigger wheel from www.trigger-wheels.com which you already discovered. With that one you just have to mill out the center of the wheel.
• A thick bracket for installing the VR sensor on the engine block
• A bracket for installation of the EDIS-6 coil pack
• A cover plate for the distributor mount flange on the engine

Installation overview:

1. Turn engine so it's at TDC 3rd cylinder
2. Remove the existing ignition setup (spark wires, distributor, coil and ignition unit)
3. Mark the position of the trigger wheel and sensor mount position for the installation. If the engine is at TDC 3rd cylinder, the sensor must be aligned on the sixth tooth after the missing tooth (see image). The easiest way to do this is to first find the best mounting position for the sensor, then turn the trigger wheel until the sixth teeth is aligned with the sensor and mark the trigger wheel position.
4. Remove the damper and install the 36-1 trigger wheel on the flange at the back of the damper. Heat shrinking the wheel on the damper works quite well.
5. Install the VR sensor. The bracket must be thick enough so it won't start to vibrate.
6. Install the EDIS-6 coil pack, a good position is opposite the original distributor location directly below the chassis frame. Wire up new spark wires ("NGK 593 nnn" wires , nnn is the length of each wire, e.g. NGK 593 076 = 76 cm. Check the NGK catalogue for available lengths.) The spark plug/wire allocation can be seen in my wiring diagram (see below for URL).
7. Install the Megajolt and EDIS-6 ignition controller on a mounting plate for easy installation in the luggage compartment (see photo below for an example)
8. Wire up the ignition with the coil pack and VR sensor, install and wire up a curve selector switch below the dashboard (optional). The wiring diagram for the Dino 246 is here: http://www.dinoplex.org/PDF/Wiring_Megajolt_Ferrari_Dino.pdf
9. Recheck the wiring, then switch on the ignition and program the factory curve as first profile via the Megajolt software.
10. Try to start the engine. if everything was installed correctly, the engine should catch on quickly and start. With the Megajolt software running you can monitor the current RPM and advance.

From my experience the only tricky bit is to correctly install the trigger wheel and sensor, everything else is quite straightforward.

The next step after the installation would be to have a rolling road session where you map the engine. Start with the factory curve and then map every 500-1000 RPM by increasing the advance at each RPM until the maximum power is reached, then reduce the advance 2-4 degrees (depending on the air temperature & humidity you have while doing the mapping). The rolling road operator should know what to do so no need to worry. Keep the factory curve on profile 1 as a fallback if you decide to drive up a mountain in 4th gear using bad fuel

good luck,
Adrian
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John,

use a 5.125" universal trigger wheel with 1/2" pilot hole from trigger-wheels.com, and have it milled out for heat shrinking it on the damper (1/10 mm smaller than the damper axle diameter). See picture for finished trigger wheel and damper with milled area for mounting.

Adrian
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For my 308, I machined material off the back of the damper and slid the 36-1 wheel over and machine 3 slotted holes to the wheel itself to allow for some physical adjustment of the wheel. Note: the megajolt software also can control the adjustment a bit if the wheel is off alignment a bit.
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The ideal position is in the middle of the crankshaft to avoid any flexing of the axle which varies the reading by some degrees. For a retrofit that is not a real option but you don't loose that much precision, maybe up to a degree or two at the end of the axle. You don't want to install it on the outside of the damper if possible (even though its the easiest solution) as the rubber between the axle and the damper element will add some degrees of variation too, especially with an old damper where the rubber started to shrink or disintegrate.
So installing the trigger wheel on the axle behind the damper is the best practical option if there is enough space.

You don't really need to weld or screw on the trigger wheel, heat shrinking is easy and that's how the industry is installing trigger wheels and even starter gearwheels. The fine tuning is then made by the sensor to tooth position.