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Many years ago my father had an 8 cylinder GM HEI distributor machined to fit his type I motor, as it turns out about the same time someone else did the same thing and had them for sale. He then removed 4 of the terminals in the cap and , walla, 4 cylinder high voltage ignition, with a large diameter cap to reduce internal arcing and a really hot spark. He has this on a over 2L motor with dual IDA's and a hydraulic cam/lifters(another post subject).

Just wondering why I'm not seeing more/any of these? I'll hopefully be taking possession of of said car in the next couple of months and can have more details and pics to add.

My guess is that full authority ECUs are so cheap now that people go COP or wasted spark coil packs if they start messing with the ignition system?

HEI proved to be a little too hot for long term reliability, and GM moved on...

Later coil designs like the LSx coils max voltage was only ~45kv, but the energy delivered/length of spark was several times what HEI was, without causing insulation breakdown issues like HEI did.
Of course ditching the distributor/cap/rotor etc and the longer duration spark also did wonders for reliability and emissions.

Today, if I was still intent on using a distributor, I'd use a Mallory or such set up with a trigger wheel, and the Ford 460 cap and body adapter, with a programmable ignition setup of some sort.
Coil: IGN1 or IGN1A or OEM Mercury Marine equivalent...almost the voltage of HEI with likely 10X the energy.

I have exactly that sort of cap/rotor setup I hacked up as a one-night project years ago still sitting on my desk.
The Mallory optical trigger wheel currently has a 16-1 trigger pattern machined into it, works for full sequential operation with Megasquirt and many other EMS. I have never fired a plug with the cap/rotor setup, but I could...

I would still very much like to see the HEI conversion on the buggy in detail.

When I get it I'll deff post up pics and info. I'm strongly considering getting the MSD module for the HEI dizzy, as it adds an adjustable RPM limiter and the multi-spark(at lower rpm's of course). My father built this motor about 15yrs ago, carrillo rods, Okrasa crank, not sure what the heads are. I do know he went with hydro lifters/cam and IDA's. He says the motor is docile in town and is built for and has been taken to 7K rpm. I was seriously considering MS for this car, but after researching and finding out what the IDA's cost, I've decided to stay with them. Once I get the car and can get all the info from my dad(and write it down), I'll know more and post more.

From what I gather, it was a fairly easy bit of machining to make the actual dist fit the VW motor. He dropped it off at his machinist and they did the work, as he didn't have access to the machines needed.

IMHO for NA use fully programmable ignition alone will get you most of the performance advantages of a full EMS...
Although the IDAs would make mighty fine lookin ITBs

An MS(x)-extra setup would control that hybrid HEI/MSD setup just fine, with full timing control and excellent datalogging.
A Microsquirt v3 would likely be ~ideal, and can be fully sealed and comes with an 8' harness w/automotive grade AMP connectors. ~Cheap too, as just has 2 spark control outs, but you need only one.

Of course one could ~completely hide the injectors in the air cleaners shooting down the bores ~like a TBi setup.

I just switched to E85, even manually tuning the EMS to allow for it took ~ 1 minute.
Liked how it ran so much I spent the $60 for a new GM ethanol sensor and pigtail that will hook up to the MS for automatic ethanol % blending between the two maps, and programmable ethanol% based added timing etc.

Yes, I've followed some of your posts. I had an MS1 on my Rabbit, but since it got killed, I'm moving on to the Bug. With the way it is setup right now, I plan on getting a number for it from a local dyno (that is fairly accurate) and go from there. But, I'm looking forward to this car, last time I drove it, nearly 30yrs ago, it had a 1776 with a prog Zenith and it was a blast. Now, it should be down right fast. And the old school way my dad built it is how it's going to stay for some time. He used to chase V8's up the Salt River Canyon between Phoenix and Show Low. They would be mad by the time they got to the top, cause they couldn't lose the powder Blue Bug.

I do like how the GM HEI was so self contained, coil, module, 1-wire, and apparently quite tunable with centrifugal and vacuum can. But there is no reason to do so unless you really like it.

Well, my dad is also a Chevy guy too. So, yes, he likes it. And from what he tells me, the car runs very well, it's been in storage for about a decade, so the carbs will need cleaned out and the rear main seal had a small leak before it was put away, and then there's all the other stuff that needs looked at before it's drive-able again.

Well, the car is here now and I was wrong about how long it was in hibernation. Instead of the decade I earlier posted it was more like 17yrs!! It needs a ton of work. And it appears the motor is seized. So, this winter I'll be pulling the motor out and apart to see what neededs to be done and also recovering the Recaro seats. Cosmetically the car is very rough, as the paint under the hood bra peeled and door cards warped. But, I am only really concerned about the seats and anything mechanical, looks can be damned for now. I'll get some pics of dizzy and such for this thread and have to start another in the proper section for the rest.

Well, After removing carbs, they are 44IDF's, not 48IDA's. Kind of a let down. He built this motor so long ago, he had forgotten this detail.

I'm still going to get some pics of the dizzy up, just not sure if you want to see it in 17yrs of dust/dirt. It'll be a little while before I can drop the motor and get it on the stand. Still need to make room for it(motor) in the garage. Too damn much water cooled stuff and other junk.

Yes, of course we want to see it!

OK, here we go.


The engine bay before I removed carbs and alt and oil filler/breather box.


And some closer shots of adaption to VW drive.




Mods to inside to make it 4 cylinder. Looks like he removed half of the points from the outer ring.

No vacuum advance huh ??? And double o rings , smart.

Jack

Jaxdream wrote:No vacuum advance huh ??? And double o rings , smart.

Jack

Dual carbs, so vacuum could be limited, but with IDF's there could be a port for it. My father built this particular motor about 20yrs ago, and has been building/working on ACVW's since the late 60's early70's. And from what he tells me, this motor would pull from low rpm's in 3rd/4th gear in town and rip over 7k rpm when asked to. So, the adv curve must be good for it. I plan on getting it running in current trim and then going from there. I have been reading/learning what I can on the ACVW forums, and from what I gather, there is not much I will need to change, if any at all. Motor-wise or suspension-wise, he knew all the good tips and tricks and the interior is/was perfect(just needs to be rehabbed).

Motor is ready to run. Should be starting it in the next day or so.