Hi all,

Only recently discovered this forum - it's fantastic!

I'm in the process of installing a megajolt distributor-less ignition system in my morris mini 998 (modified). Have all the necessary parts and am ready to install the system.

Am keen to avoid electrical interference issues (from items such as alternator, sparkplugs etc).

Would be interested to know what others with this system have done in regards to
- location of megajolt
- location of edis module
- location of coilpack
- routing of wire from crank angle sensor?
- routing of wire between megajolt and edis
- routing of wire between edis and coil..
- whether wiring between EDIS and coilpack should be shielded?

My current thoughts are to:

- mount coilpack very near to existing distributor (and re-use leads for a hot-swappable system back to distributor if i ever needed to. (i'd like to keep length of HT leads to a minimum also))
- mount megajolt under dash as per recomendation from autosportlabs. (inside cabin)
- mount edis under dash in very close proximity to megajolt (inside cabin) with shared power and earth pickup points
- use shielded wire from edis to crank angle senor (grounded at edis end only)
- use shielded wire for PIP/SAW communications between megajolt and edis with grounding at megajolt end only.
- use un-shielded but twisted 3 wire (heavier gauge) wire from EDIS inside cabin to coil pack in close proximity to existing distributor (probably attached to back of alternator bracket?).
- use a relay with 30A fuse for clean power to EDIS, megajolt and coil with main feed directly from for back of starter solenoid post , relay being controlled by ignition circuit
- will be running resistor (bpR6es) sparkplugs and Magnicor HT leads.


Anybody see any issues with this setup or can anybody provide any details as to routing of wiring etc etc?


Thanks in advance


Nick






Am considering having coilpack

Hi Nick
All sounds OK except the leads have a different end on them and may not be swappable between distributor and coil pack?
I mounted my coil pack near the back of the alternator, onto the alternator bracket.
My biggest issue was getting the correct location for the sensor to line up with trigger wheel

_________________
1969 Cooper "S"
1967 Mini Deluxe
1973 Clubman Van (the fleet spare)
1978 ex 1275 LS ("Wizard" Eaton Supercharged)
2015 HSV GenF GTS(occasional drive & tow car)
2019 MINI F55 Cooper S

I've got my VR wiring (shielded) running around the radiator, into the cabin with the wiper motor wiring, and have my EDIS and MegaJolt sitting on the dash. Well, the EDIS sits on the dash panel, the MJ is fixed to the Weber Box with double sided tape. Running the VR wiring that way meant that it's basically on its own for 75% of its run. Sure, it's shielded, but that doesn't mean I need to work the shielding hard! It's also a much shorter run than going around the engine bay and back up (even if some will argue it's not as neat).

I have unshielded wiring for the coilpack from the EDIS, but I've mounted my coilpack over the clutch cover where the coil used to be. And I have custom length plug leads to suit.

The leads? Can retain them if you use the Hyundai coil pack instead of the Ford one... But I'm guessing you're going new ones (would be a waste not to update).

And I went resistor plugs, but stayed with 5's instead of 6's (running unleaded). I'm running 0.040" gaps, running rich according to the plug lands, but with a beautifully white and clean porcelain insulator on the plug. Haven't changed the tune (well, yes timing, no to mixture) since changing to the MJ, and before installation it was running a GT40 and blue electronic module in a 43D4 with 0.025" gap, and fouling plugs. So much better, so much stronger a spark!

I too use a Hyundai coil pack, from a late model Getz. Much better in my opinion to be able to use normal leads!. Megajolt would have to be the single best mod I have done, originally used for a supercharged engine & now on a normally aspirated A+. Much easier cold starting & when tuned properly is so responsive. Sounds like you should have no trouble with your planned setup.

Ash.

_________________
----------1984 Mini Mayfair with not much 1984 Mayfair left of it!-----------
----------1968 fake Cooper S that messed with a tree -----------------------------

Thanks all for your replies and your advise. I am happy to report that I had already purchased a brand new Hyundai excel coil pack rather than a ford pack.

Pleased to hear that running the mj and edis inside the cabin is a viable setup.

You are quite right that setup of the trigger wheel takes a while. Decided to replace the timing whilst I was in there which is now done but did slow me down a bit.

Now onto the electrics.....

Cheers

Nick

Hi michaelb, tadhg, m1100s.

Good progress has been made, thanks again for your advice.

I now have a running Megajolt and EDIS setup.

Distributor is still in situ and I can swap between a dizzy to the non-dizzy ignition system in less than 5 minutes for redundancy purposes.

My setup....
1. Both EDIS unit and Megajolt are installed in the passenger side "glove box" inside the cabin. I've kept the PIP/SAW cable length short and it's fully shielded cable that's earthed.
2. Earth is shared for EDIS and Megajolt. Coil is earthed separately.
3. Coilpack is mounted on back of alternator bracket (and is the only part that needs to be physically swapped out to revert to the old distributor points system).
4.. Crank angle (VR) sensor cable is routed under and then behind the radiator and then via the firewall grommet for the windscreen wiper wiring. It's only grounded at the EDIS end (so it doesn't become an engine earth strap). Seems ok so far - but haven't tested with wiper motor running yet.
5. Wiring linking EDIS to coil is routed along top of firewall and then down clutch side of motor to keep away from crank angle sensor wiring.
6. Both EDIS and Megajolt share common ground and +12v.

Oh and quick question.... Is the occasional random jitter in the ignition advance normal with megajolt?

So far I'm getting a rock-solid 10BTDC spark with only the EDIS unit attached (running in limp home mode). There is no jitter or deviation from 10 degrees BTDC here throughout the lower rev range - so VR sensor and cabling seems good and no interference seems to be occurring with EDIS / VR sensor / coil pack by itself.

With megajolt connected also seems to work very well - just the occasional jitter/scatter in the timing (once every approx 5 seconds or so - in the same lower revr range as before (and even just when the motor is running at idle) but not in any regular pattern).

I am using the default megajolt map at this point. ( As I've not yet got access to a rolling road dyno to setup the curve more accurately).

How am I checking the advance?? I'm looking at the timing using a non-computerised timing strobe on the crank - I figure that this is the ultimate source of truth as it's what the spark plug is seeing as opposed to what the computer believes it is doing....

Pretty sure it's not MAP related - as i saw this jitter when the MAP vacuum line was disconnected from the megajolt.

I'm thinking of trying the following to see if this "jitter / scatter" goes away:
1. - I'm running suppressed leads but not resistor spark plugs just yet - I will change them over to "R" resistor plugs to see if this makes any difference. (Not sure if the megajolt unit is more succeptable to noise than the EDIS unit. )
2. - Routing the PIP SAW cables so they are as far away from other wires as possible.


Anything else you can suggest or is the occasional "jitter" in advance normal???

Kind regards

Nick

I hadn't seen any jitter with mine before removing it (megasquirt), but one thing I did was create a map that was 10 degrees in all load and rev ranges so I could see that the timing was consistent everywhere. Testing with the timing light the same as you, the pointer on the wok was always at the same place. I suggest you try that as you may just be seeing some legit (but slight) advance changes

your install is utterly by the book, mine was about exactly the opposite, the only shielded wire I used was from the crank angle sensor to the EDIS

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Good idea! I shall do that. Thanks.

10 degree map and timing is steady. must have been legit timing changes. Thanks again for the suggestion.

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