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Flexible Ignition solution.
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Post Flexible Ignition solution. 
Hello all, an original v1 megasquirter here coming back a few years later for a bit more (MS still squirting great). I'm ready to ditch the points and go digital but here's the problem. The megajolt lite jr may be a bit too complicated for my needs. For my old classic vehicles and motorcycles: I would like to gain the digital ignition timing control capabilities but not necessarily go for the full the Ford EDIS solution. I have 3 motorcycles and 2 cars with points and im really tired of fiddling. My MegaSquirted fuel injected land cruiser really demonstrates how quickly ignition points performance falls off between tune-ups. I would like to build one solution for my applications and keep my distributors, coils and wires etc...

Locked distributors with a nice VR sensor rising and falling with the distributor lobes would be a nice solution, but does this provide enough resolution for timing control? or does one need to go to the toothed wheel options for any kind of accurate timing advance strategy (rpm & map tables)?

Complicating the problem, the motorcycles have kick starts as well, I know VR sensors have a minimum speed threshold in which they will provide a good signal. As far as I understand it, slow speeds mean bigger diameter wheels to help out the VR sensor (which has packaging problems for a motorcycle setup).

A Hall sensor setup would require building a shutter wheel but has the advantage that it can be very small, im just not sure how much "dwell" (well what the ratio between open\close shutter openings) should be. And im not sure if megajolt can handle a hall sensor input.

Is there anything that is lighter and younger than megajolt lite jr??

As usual, all advice and suggestions are greatly appreciated. Keep on mega(whatever)ing.

71 FJ40 land cruiser 6 cylinder
69 Austin Healey Sprite 4 cylinder
73 R75/5 BMW twin
75 R90s BMW twin
75 Honda CB 400 four (double points, oh the humanity)

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Hello and welcome;

We have been discussing this topic here:

Regarding your question on accuracy: Many distributor based setups have very coarse timing signals, typically only one signal per ignition event. Timing skew during rapid acceleration/deceleration seems to be the biggest weakness. Correspondingly, steady state to low RPM changes should be acceptable. And, of course, timing scatter due to backlash in the drive system is a perennial problem. By modern day standards, distributor based ignition can't be considered "high performance".

If you are the least bit concerned about this, go for the crank fired solution- the effort to mount the trigger wheel and sensor is paid back many times with the performance / driveability improvements!

Hope this helps.

Brent Picasso
Founder, Autosport Labs
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