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electronic ignition
02GF74 - 13/3/07 at 08:43 AM

if I were to contemplate fitting electronic ignition to a cross flow, what bits do I need?

1, coil pack (the square lump with 4 igntion lead sockets)
2. trigger wheel
3. VR sensor for item above to figoure out crank position

now it gets a bit hazy coz I don't know ..

4. EDIS - is this the module that uses the input from the VR sensor to fire the coils?

Is it programmable or is there some extra box that is and then fires the EDIS

??? in the meantime I'll have a gander on the megasquirt site.
oh, the reason for electronic ignition is they my maplins ignition amp seems to be faulty so might as well go the whole or half-whole hog.

[Edited on 13/3/07 by 02GF74]

miegru - 13/3/07 at 08:45 AM

if you go this way I would advise you to go all the way and go injection also.

HUGE difference

02GF74 - 13/3/07 at 08:48 AM

^^^^^ yeah, that is longer term (got the TBs )

so those that make a difference as to whether I should go straight to megasquirt without the inermediate step of megajolt?

JAG - 13/3/07 at 09:12 AM

Get your Megajolt sorted out first. That will make a major improvement in how it runs - you may decide that's good enough.

You'll need an EDIS (this fires the plugs and is a combined ignitor unit and limp home management system) and a Megajolt to manage the signal from the VR Sensor and tell the EDIS when to do it's thing.

My friend has a Megajolt on a 1.8 Zetec with twin 40's and it works superbly well.

[Edited on 13/3/07 by JAG]

02GF74 - 13/3/07 at 09:16 AM

is megajolt a DIY bnoard with microcontroller (similar in idea to Megasqiret)?

does megasuiret have megolt functionality or do you need both modules?

????

tks - 13/3/07 at 09:57 AM

Mega squirt is: Injection and Spark

Mega Jolt is: Spark only..

both use the EDIS module incl. coilpack
VR sensor and the trigger wheel.

Tks

andyace - 13/3/07 at 12:36 PM

I might go for one of these, the EDIs unit is contained in the same housing as the Megajolt unit.

http://www.kimmins.info/

Also see this link for useful info on a megajolt fitted to a 7

http://www.cate1.co.uk/megajolt/

MikeRJ - 13/3/07 at 01:13 PM

quote:
Originally posted by 02GF74
now it gets a bit hazy coz I don't know ..

4. EDIS - is this the module that uses the input from the VR sensor to fire the coils?


The EDIS module is what does all the clever stuff, interfacing the VR sensor, time/angle conversion, dwell control, coil drivers etc. The engine will actualy run with just the EDIS, VR sensor, Trigger wheel and coil pack, but the timing will be fixed at 10 degrees BTDC.

The Megajolt box just looks at the engine speed and load (via a MAP sensor or throttle pot) and determines what advance is required from the ignition map programmed into it. It then sends this information to the EDIS module encoded as a pulse of variable width over a simple interface. The actual megajolt box is really a very simple controller, not much to go wrong if it's been built and programmed properly.

02GF74 - 13/3/07 at 06:36 PM

thanks for replies.

so can I run megaSquirt for just igntion without an EDIS to trigger the coil pack and without any fuel control? ( the latter achieved by not connecting any injectors)

MikeRJ - 13/3/07 at 06:52 PM

quote:
Originally posted by 02GF74
thanks for replies.

so can I run megaSquirt for just igntion without an EDIS to trigger the coil pack and without any fuel control? ( the latter achieved by not connecting any injectors)


Yes. You need the Megasquirt 'n' spark firmware and you will need to add an extra coil driver to the PCB (not difficult). You can then program the system to use almost any common trigger wheel, and simply ignore the injection side of things until you are ready for it. Quite a few people have done this on the MS forums.