[jseabolt]

First of all, BIG THANKS to whoever mentioned using the 5 pin HEI module as a cheap alternative to an MSD system. I did this on my Yugo turbo and it works great. I replaced the 1.5" exhaust with a fat 2.25" and the car screams now. It will spin the tires in 2nd gear at full throttle.

Here's how I adapted the 5 pin module to a Bosch distrbutor:

GM 5 PIN HEI module pictures by turbofiat - Photobucket

My question is if you have a car with points, can you use points to trigger an HEI module? If so how would you wire it up?

I've seen some systems that take the load off the points which allows them to hold up longer and it may be exactly what I'm trying to do.

Any idea if this is possible?

[LATECH]

well, the GM HEI needs a small voltage 1-3 volt and it must be an AC signal.The module fires the coil on the descending voltage spike of each pulse of the magnetic pickup.
All you need to do is replicate that voltage/sine wave characteristic with a set of points and you are good to go.

[jseabolt]

Thanks for explaining how the HEI system works. I wasn't sure.

As much as I'd rather deal with a carburator over electronic fuel injection, I despite points. Hate them with a passion.

Whenever i get a car with points, the first thing I do is rip the out and convert it over to electronic ignition. Like I did on my 68 Fairlane.

With electronic ignition you either have spark or no spark. Points it's either a good spark, weak spark or no spark at all.

Another thing I hate about points is I changed out a set on a lawnmower once and could not get it to fire. Then a friend suggested I close the gap a bit and not go by what the factory says and it fired right up!

Just recently a friend dropped off a 74 Fiat X 1/9 he had purchased in Maryland that had died on him somewhere in Virginia on his way back to Knoxville, TN. I offered to let him drop it off at my house in Kingsport to avoid paying an extra 100 mile towbill and told him to give me a few days and I'd see if I could figure out why it wasn't getting any fire.

It would get fire from the coil to the distributor cap but not past it. I first tried a different coil and it fired up but idled rough. Then 10 minutes later would try to start but wouldn't run.

Now it's got a very weak spark to the plug wires but wouldn't fire the plugs.

I tried new plugs. Nothing. So I decided to see if the condensor was bad.

My guess was because the spark was so weak, it couldn't jump from one part to another. And for ever component electricity had to travel through was resistance in the system so by the time the spark made it to the plugs, they wouldn't fire.

Due to limitied access to the condensor (the car is a mid engine model) I couldn't get to the screw on the condensor so pulling the distributor was my only option.

My friend was going to convert it to electronic ignition when he got to Knoxville but since he didn't make it I decided to do it for him. Since pulling the distributor is BIG DEAL on an X 1/9.

So I used a distributor, coil and control module scavenged from an 88 Yugo parts car. Car runs sweet now!

The main reason I ask is I'm getting a Trabant 601 and the first thing I want to do is get rid of the points system and convert it to electronic ignition.

This engine has a 2 cylinder 2 stroke and uses two coils (one of each cylinder) and uses two sets of points (for each cylinder).

I can get a kit to convert it over to electronic ignition but it's expensive (from Germany) and was wanting to see if there was something I could use to take the load off the points so they wouldn't wear out as quickly. If possible.

The engine uses a breaker plate which is somewhere on the engine (like a motorcycle) and does not have a distributor.

Trabant 601 > Spare parts > Electrical system > Ignition

[sparkchaser]

Yugos, Fiats, and Trabants! You deserve an award for keeping those things running. My hat is off to you.

[DanielC]

In the 1970's Radio Shack had a kit you could assemble, and solder, that would use points to trigger an CD ignition box. It used the stock coil.

I believe the magnetic pickup used on more modern cars works by sensing a polarity reversal as the magnetic pickup passes the sensor in the distributer.

In the Datsun world, there is a distributor with a module on the side of it, called a "matchbox" distributor. Occasionally the matchbox goes bad, and if a new one cannot be found, you use a four wire GM HEI module, and mount it on a heat sink. Two wires go to the pickup in the distributor, one wire gets battery positive, to power the electronics, and one wire goes to the negative side of the coil. The module is grounded.

So, if you can get some sort of a magnetic pickup in the Fiat, or the Tribant distributor, I would think it would be pretty easy at that point to use the GM HEI module.

[olaf]

Jseabolt, there are two different actions going on when using an electronic distributor vs a points distributor.
The electronic distributor send a pulse to the HEI module when the reluctor passes a magnet, as if contact was made.
In a points distributor, the points open to collapse the magnetic field in the primary windings in the coil, acting opposite to an electronic distributor.

The old Ford modules work opposite the GM HEI module, and can be used with points distributors. In a discussion in another forum there were also mentioned that a '76 Toyota came with a hybrid points/electronic system, and I am sure there were others too. The downside regarding the Ford module, is that it probably doesn't have the same excellent reputation as the GM HEI module has...
One advantage of using an electronic module with points, is that the module only requires that the points open at the correct moment, it doesn't care how much and how long, so maintenance becomes a lot simpler!

See these links for some adaptions, they are for motorbikes, but works equally well for car engines:

Points to Electronic Ignition Cheap & Easy - ADVrider

General Motors HEI Ignition Module For Points

Olaf

[jseabolt]

Thanks for the links! The Ford module looks like it would require allot less components to make it work. Despite I like the simplicity of the HEI module.

Here's my HEI 5 pin conversion I did on my '87 1500cc Yugo I turbocharged:



And a write up on how I did it. I'm going to be getting rid of my Jacobs Boostmaster and going with this module instead since the Marelli coil pack/distributor was designed for a 4 pin module to begin with.

GM 5 PIN HEI module pictures by turbofiat - Photobucket

Back in the day, these Bosch modules were around $200. They fit a variety of European cars in the 1980s like BMW, Audi, Porsche, etc. then someone discovered a $15 4 pin HEI module works just as well and it does. Just a matter of getting the polarities correct.

Everybody kept telling me to spend the $700 on an MSD system but I only needed about 10 degrees retard and the $35 module and $25 pressure switch work just as good.

[olaf]

The 4-pin GM HEI module is first class for most applications. I am very satisfied with my installation on the Slant Six engine in my Dodge Aspen Wagon, instead of the stock Mopar unit that uses a ballast resistor. I use the HEI together with an ordinary Standard e-core coil, used on Fords and Mazdas. I use NGK UR45IX spark plugs, that comes pre-gapped at .059"! Starts every time and run like a clock!

Other members who want to switch to HEI: Consider using a relay to feed current from a good source to the module. It draws somewhere in the region of 8 amps or more continuously, and use a good heat sink along with the heat transfer paste that comes with the module, it turns a lot of the amps into heat!

Olaf