Mopar Muscle Association UK

One for Dave999

OK - Engine out, engine gone, 12v-all-in-1-MSD-dizzy gone with it.

New engine in, just wiring up.
As I looked at the newly supplied orange box and the ballast resistor I just got a sinking feeling remembering all the pain. Do I REALLY want to go down this road again...? I remembered in the past the view of 'Get rid of the ballast, stick an HEI in there, 12v to the coil - boom - off you go.

My coil is an MSD blaster2 - so 12v - I really want to feed it 12v. Reading up over the weekend I think its actually not too bad.
Using the voltage reg that I have (which fed the 12v MSD previously) I reckon the new setup could look like THIS.

Could someone sanity check it. Seems too easy. But given the coil and voltReg are both suitable...

thanks !

hmm

https://www.streetmusclemag.com/tech-st ... to-gm-hei/

OK brain trust. Not a great day. Thought this would be it - fire up and shakedown.
Lost a long time with no spark.

I am pretty confident its all wired up correctly.
I can see 12V at the coil as you'd expect. But I have no spark.

Long story short - I suspect the HEI module - it just isnt switching. My understanding is that the HEI takes a reading from the dizzy and effectively 'pulses' the negative connection down to the coil.

I can read the 12V at the entry to the module - but nothing from the other end.
Everything else looks fine. Car cranks etc - just sparkless and apparently nothing from the ignition module.

Anyone Herts/Bucks happen to have one I can test ?

OK - despite no feedback, updating this one for reference (which is what this forum is GREAT for)

Sorted.
Long story short -

1 - The diagram at the top is correct. This is a simple way to ditch the ballast and the orange box.
2 - HEI modules appear not to be created equal. I bought 2 really cheap ones just to get it running and test the theory - both were DOA. Eventually I borrowed one from a scrap HEI distributor and that worked. This is where I lost the most time.
3 - HEI modules are super sensitive to having a battery with enough oomph. Although charged, its time for my battery to be changed - although showing 12.5v, it was dropping to 7v-ish on cranking - and this just isnt enough to fire. Swapped it in for a fresh borrowed battery, cranking voltage jumped to 9v, spark achieved.

Thread closed [hopefully]

oh missed all of this..... which is odd as i click "new posts" almost every day and have a look...!
i've been on the board since may 6th and this has not been flagged as new since.... and when i look today 20 new posts.... no weekend in recent memory has had 20 new posts. Mmmmmm i'll clear cookies


yeah you need to spend £20-30 on a branded one

id run it with this coil

https://www.rockauto.com/en/catalog/che ... +coil,7060


Make sure you run it on a heat sink.

and i [protect mine with a diode

lots of stuff here
the link to slant6.org is good as well, slightly excessive given an installation as shown in your diagram works perfectly well... but good read
daniel stern/slant6dan is a bit of a prickly individual but is head is screwed on and is heart is in the right place...he's a very particular kinda guy.. belt n braces n hairy string every time...

https://www.moparuk.com/forums/viewtopi ... 21#p667321


couple of things
don;t dismiss broken as broken just yet
1) tollerance stack... the module and pickup in dizzy may be mis matched
2) some modules were designed for mounting under a coil in cap set up and the piclup wires connect the other way

no rhyme or reason to it


modules
https://www.ebay.co.uk/sch/i.html?_nkw= ... &_svsrch=1

https://www.ebay.co.uk/sch/i.html?_nkw= ... &_svsrch=1


or standard
https://www.ebay.co.uk/itm/256264292476 ... BMzoCo_Nxl


if you want the document i sent to Steve explaining why HEI kicks a considerable amount of ass for little $$ outlay... let me know

you are building an ignition that one australian supplier had the gall to sell in the early 2000s for $480 rebuilt dizzy with a module on the side...and a nice sticker over the delco part number.... needless to say easier $$$ ways to do it..

Dave

You see I though this one would be right up your flagpole !! hahaha

So the modules that didnt work - cheap-as-chips-ebay-finest (just to prove theory) - but both DOA. I really do think they are DOA.
The one I managed to get working was out of a scrap MSD dizzy. Pull the rotor off and the module below looks exactly the same. Couple of plugs and its out.

I have 3 AC Delco ones on the way from US - having failed to find any outside of ebay £9.99 in UK - didnt realise they were not listed as 'HEI module'. Still - never mind. They will be here in a day or so.

Funny think was I KNEW the module was the questionable bit - but 2 of them... threw me. (ignore temp wiring)
I'd even double stacked them anticipating a roadside failure at some point. Lots of space , heat paste, airflow and gaps.

Diode is a good shout.

nice one

that wiring will be fine....

have a little squizz at the diode stuff on the linked page

Dave

Will do.

Lucas one on the way too. I now have 4 modules incoming.
Not that ignition woes have scarred me for life or anything.

On a serious note, in 20yrs my single biggest irritation with this car, by a MILE has been ignition.
Points , orange boxes , silver boxes, HEI, All-in-ones - been everywhere.

i too have had my ignition trials

this is where i have landed. 2 solutions one both or neither of them might work

original solution
1) take dizzy, take it to bits clamp shaft in vice, put a degree wheel over where the rotor fits, fit rotor twist it so it activates the advance, measure, adjust advance travel against your degree wheel. 1 degree in the dizzy is worth 2 at the crank so added a small brass bush to its resting stop, so that the distributor added only what i needed. in my case 6.5 degrees. i could then set it at 15 initial and have 28 total.. 6.5 x2 is 13 13+15 is 28* total, this was done totally focused on not running vacuum advance... then i saw the light......

i then stuck the vacuum onto manifold vacuum via a fitting on just 1 carb, below the thottle plate, A La Alfa romeo alfasud via a pulse smoother, so it pulls in all the vacuum advance at idle and a small proportion at cruise... advance at idle....mental, but it likes it...advance off idle just the mechanical advance at lift off throttle, at speed mental.. but i can now go an awfully long way on idle mixture with my foot off the gas.... i can roll up to the traffic lights from about 10 miles away, that sluggish weightyness when you lift off the gas is gone, much more like driving a smaller nippy little car .......

2) take a standard dizzy, set it up at total mechanical you need 28-34* 36 in some rare cases, which on mine is 28* check what it is at idle, about 4* BTDC swap springs and until you get 15 degrees at idle then plumb in the vacuum as before.

both achieve more or less the same sensible initial for cam/compression and modern petrol same old total mechanical advance

15 initial bolstered by vacuum up into 30s at idle speed
15 -28 off idle up to max rpm

the second way is achieved just with springs , the first involved mechanical changes to the advance mechanism at the mo. i still think version 1 was best, but have not done anything to version 2 really to make it better. Waiting for mr Moroso to send a kit of springs and small pieces of plastic .

i run Hei with an HEI coil and plug gaps of 45 thou.

HEI failures i had a few and my tacho used to flip out occasionally pinning the needle to the end stop, until i put in the diode.. i was always suss, that it was my alternator killing the modules.... there was nothing wrong with the alternator up to the point where the brushes wore out but i was very suspicious, we are running something closer to a computer in a car with an electrical system only slightly better than a ferguson tractor .

Dave

Soooo - AC Delco ones arrived today. Guess what ? Stamped up as GM OEM !
I now have 3 of these and a Lucas one on the way. Belt , braces and sock suspenders.

Good tip on the Diode - Looking at it now. Seems a no brainer; will update diagram for reference.


sooo - like this ? (green)

Yeah. That should do the job.

Those GM ones should be good.

Dave

Mounted. Double stacked. Trimmed. Spare spade ready for new diode. Fingers crossed...

OK - Final update.

All works 100%. Car runs beautifully.
Wiring diagram above is good for those who come later and make the swap.

Installation has double stacked HEI modules just-in-case. Only thing I have to add is the diode for protection (on its way).

Excuse the quality of the pic - but final install, with earthing and airflow.

Thanks Dave999 - as always...

yay!

sorted

dave