Not Anumber
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| posted on 27/1/14 at 10:50 PM |
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Megajolt plus original ignition fallback ?
Whilst wiring in the Megajolt I was about to chop out the wiring to the original spark unit, dizzy and coil when I had a thought about retaining the
distributor based ignition.
I could:
Remove and flog off the electronic dizzy, leads, spark module, single coil and associated LT wiring that make up the original ignition. Then install
simple point to point wiring for the Megajolt (& fit a chopped down dizzy base for the pinto's oil pump) Or
Remove the dizzy, leads and single coil, leave the LT wiring for them intact but tucked out of the way. Or
Keep the original ignition intact with the HT leads from the dizzy tied out of the way so it can be brought back into service by swapping the leads
and flicking a changeover switch.
The coilpack sits on a bracket off the rear of the cylinder head so there's no need for me to fit it where the dizzy would normally go. It wont
make any difference to the amount of work or cost and just a few ounces weight difference to go for the full parallel system failsafe.
My only hesitation is that I haven't seen many others doing this and wonder if there's a reason why ?
Whats the consensus ?
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snapper
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| posted on 28/1/14 at 03:13 AM |
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Megajolt instal already has failsafe as EDIS provides 12 degree limp home on its own if Megajolt fails
What engine? If Pinto dizzy provides oil pump drive
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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snakebelly
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| posted on 28/1/14 at 09:09 AM |
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I seem to remember the fail safe timing for the EDIS will be 10 deg rather than 12 I think?
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mcerd1
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| posted on 28/1/14 at 09:19 AM |
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^^^ what they said
the EDIS4 has a built in 'limp home mode' (although I thought it was 10° fixed...) its the one major advantage of using MJ + EDIS instead
of the fancy modern all-in-one units 
you can try this mode by just unplugging the MJ ecu, in fact most folk recommend getting the engine running on the EDIS alone before even fitting the
MJ 
(that way you know all the basics are working before you add the fancy bits  )
a cut down dizzy to to drive the oil pump is all you need
[Edited on 28/1/2014 by mcerd1]
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r1_pete
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| posted on 28/1/14 at 09:35 AM |
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If you're worried just carry a spare EDIS unit.
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Not Anumber
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| posted on 28/1/14 at 11:42 AM |
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My thinking was mainly to guard against coilpack failure. Ive experienced two coilpacks go down suddenly in the last few years both on relatively low
mileage cars whilst the only isue Ive had with single coil systems is a gradual loss of spark efficiency, never failure. I drove cars with single
ignition coils for many more years, for many more miles so feel I can trust them more. (Mind you they were both VW group cars so not sure if that
says more about the brand than the technology)
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mcerd1
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| posted on 28/1/14 at 12:17 PM |
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^^ not heard of many coil pack failures with the ford ones of either type (early or late)
and from my own experience I just sold my focus tin-top at 136K and nearly 14 years old with what I'm pretty sure was its original one from the
factory still working perfectly
but nothing says you can't carry a spare one if you like - they are fairly cheap too
[Edited on 28/1/2014 by mcerd1]
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matt_gsxr
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| posted on 28/1/14 at 05:53 PM |
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quote:
Originally posted by Not Anumber
My thinking was mainly to guard against coilpack failure. Ive experienced two coilpacks go down suddenly in the last few years both on relatively low
mileage cars whilst the only isue Ive had with single coil systems is a gradual loss of spark efficiency, never failure. I drove cars with single
ignition coils for many more years, for many more miles so feel I can trust them more. (Mind you they were both VW group cars so not sure if that
says more about the brand than the technology)
VW/AUDI had a massive cock-up and loads and loads of coil on plug failures. Normally these are robust parts so just one epic fail by VW.
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snapper
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| posted on 28/1/14 at 06:10 PM |
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Majority decision 10 degrees it is
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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mcerd1
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| posted on 28/1/14 at 07:52 PM |
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quote:
Originally posted by snapper
Majority decision 10 degrees it is
well it should be assuming you set the VR sensor at the right angle relative to TDC
(i.e. the EDIS will think its 10°, but that might really be 12° if your VR sensor is a couple of degrees out)
[Edited on 28/1/2014 by mcerd1]
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Not Anumber
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| posted on 29/1/14 at 11:23 AM |
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Thanks guys I'lll strip out the old dizzy based setup as soon as it stops raining long enough to get it running on the Mj and Edis.
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mcerd1
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| posted on 29/1/14 at 04:50 PM |
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no need to strip out the dizzy untill your ready
get the trigger wheel and VR sensor mounted and working etc...
then just disconnect the wires to the dizzy to while you get the rest of it wired in
(that way you've got it as a fall back if the weather turns too good to resist while your half way though the swap)
then once your up and running on the EDIS / MJ you can start and strip out the old dizzy (assuming you've got something else to drive the oil
pump)
have you got any base maps for your pinto yet ?
if not I've collected a few you can have a copy of
[Edited on 29/1/2014 by mcerd1]
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Not Anumber
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| posted on 29/1/14 at 05:14 PM |
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That would be great if you could share those base pinto maps. I have sent my email address.
The trigger wheel and VR sensor are in the right places, the coilpack and Edis have been bolted in so just waiting or a break in the rain to run some
temporary wiring to try it out.
[Edited on 29/1/2014 by Not Anumber]
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Not Anumber
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| posted on 4/2/14 at 10:09 AM |
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Thanks for the maps Robert.
Removing the old ignition system allowed neater and simpler point to point wiring.
It started 1st time on the Edis on test and ran well on the Megajolt just with a default map, already it's much smoother to drive than with the
distributor.
If the weather is kind this evening I will plug in the laptop and try loading ad tinkering with maps. For accuracy I should also check the trigger
wheel/ sensor alignment to see if it needs any offset, any tips on doing this ?
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mcerd1
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| posted on 4/2/14 at 12:14 PM |
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nice one
whats your plans for the dizzy / oil pump drive ?
are you going for the cut down dizzy with the coil pack mounted on top or something like this:
http://i5.photobucket.com/albums/y170/mcerd1/Dax/DSCF1936.jpg
http://i5.photobucket.com/albums/y170/mcerd1/Dax/DSCF1937.jpg
I'd like to say I made that on the lathe - but I actually got it as a strait swap for a couple of old dead dizzy's
[Edited on 4/2/2014 by mcerd1]
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Not Anumber
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| posted on 4/2/14 at 12:25 PM |
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That looks good.
Id already mounted the coil at the back of the head so got a pal with a lathe to cut off an old distributor body just above the bearing, then cut the
central shaft level and made a plastic cap to fit over it. It does the job, but yours looks neater.
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