EDIS-6 Trigger Options

[Bren81]

Gday, first post here. I Hope I have put it in the right spot and I have used the correct wording, Im still learning.

I have read the EDIS section of the FAQ but couldnt find an answer.

Short version: Can I use EDIS-6 with some sort of trigger inside a distributor, ie, half crank speed?

Long Version: I am currently planning a new setup for my car. For those that may know the vehicle model or engine it is a 1991 Nissan Patrol with the TB42 engine. It is currently a 4.2litre straight 6 normally aspirated carby with aftermarket electronic ignition (optical sensor with trigger disk with 6 even cutouts). The new setup I am planning will be multipoint EFI, turbocharged and preferably no distributor. Because the car is a 4WD it often used in mud and water, the distributor for this motor is right at the front and reasonably easy to get wet when doing river crossings. To keep the ignition simple the EDIS-6 system seems to be a good option, however I would prefer to not have a crank mounted trigger wheel for a couple of reasons, one is to keep it away from mud, rocks, sticks etc while offroad, the other issue is I am very limited for space around the harmonic balancer. There is around 5-6mm (3/8"?) between the harmonic balancer and engine fan and no room between the timing cover and harmonic balancer (I can post pics if it may help). I think I could fit a trigger wheel in there somewhere if I had to but I would probably use another system if the EDIS/distributor setup wont work.

One easy option I have if EDIS can be triggered from something other than a crank mounter wheel is that my engine did come out with EFI it has a trigger wheel very similar to the pic below but with 6 lager cutouts instead of 4

Would this be at all suitable for EDIS?

If none of this is possible can someone suggest another ignition setup using either the existing opto and 6 cuttout setup I currently have (I can easily disable the standard vac/mechanical advance) or with the above trigger wheel? My aim is simple, reliable and as waterproof as possible while still having the MS control timing.

If you think I am going about this completely wrong please let me know.

Cheers,
Bren

[kjones6039]

To the very best of my understanding, EDIS (4,6 or8) only works with a 36-1 wheel.

Ken

[Matt Cramer]

Ken is correct. You could cut a double 36-1 pattern in a distributor wheel since it spins at half crank speed. But there's no known way for you to reprogram the EDIS firmware to handle an alternate pattern. Even if you could hack the EDIS module, I doubt the chip in it supports two edged IRQ triggering needed to read the Nissan wheel.

[Bren81]

Thanks for the help guys.

I think I will look at different options.

Bren.