Fitting a HEI Module in Transistor Ignition Unit 1977 280Z

[grannyknot]

Chas, that's some great there, that should be a sticky.

Chris

[TomoHawk]

Yes, I've been reading this too. 

 

Who is offering  service to install the HEI module into the ignition box, and how fast can it be done? 

 

I looked at some alternatves to the Pertronix flamethrower module, and came up with this

 

One GM module had six pins, and one had 8 pins.  What's the difference?

Edited March 11, 2015 by TomoHawk

[TomoHawk]

Has anyone tried this wit the ignition unit from a 280Z?  I suppose It's close to the what is pictured n the first few posts in this topic, but the 280Z unit  (or the later one) doesn't have screw terminals;  it has a 6-pin connector.  You'd probably just   need to cross-reference the wires and the rest is the same.

 

Can you get a cheap (free or non-working)  ignition unit box somewhere?  I'd rather not have the car laid up while you modify the ignition box, and I'd like to keep the original ignition box, just in case.

[Captain Obvious]

I'm not sure I'm understanding your comment about the 280Z ignition box not having screw terminals, but I can tell you that the one from my 77 280 looks just like the one that Chas posted on the previous page.

 

In other words, my 77 module has the screw terminals on it.

[TomoHawk]

referring to Post #2, my 1978 ignition box doesn't have the screw terminals in the photo, or the screw terminals that are indicated in the schematic.  the connection looks more like this:

 

 

I think I 'll post an ad for a non-functional unit.

Edited May 12, 2015 by TomoHawk

[Captain Obvious]

Cool. There's some ignition module trivia I didn't know. It looks like they changed the connection scheme between 77 and 78.

 

I, like you, would assume the functionality is the same, they just change the connecter scheme. So it should be a pretty simple matter of mapping the connector pins between the two designs.

[Captain Obvious]

Forgot to mention... Since they went to the distributor mounted ignition module with the ZX in 79, it appears that the 78 module is unique to that year.

 

So in your hunt for a dead module, I'm thinking it would be easier to find one from a 75-77 than a 78. You might end up having better luck getting an older module and cutting the connector off your harness or building a little breakout connector cable to adapt to an earlier module.

[TomoHawk]

I was wondering if another model of vehicle used the same module, or one wit the same connector, that you might still find in a JY.

[EuroDat]

Hi Tomohawk,

 

It doesn't make any difference. The terminal block is differant but inside is almost the same. I don't understand what you mean by the "6th" wire? The terminal block is a 6 plug connector, but only 5 are used. The middel section on the side where you push the lock is free IIRC.

 

Connector wires:

Red - Pick-up wire

Green - Pick-up wire

Black - Ground

Black/White - 12V

Blue - Coil (-)

 

Chas

GM_HEI_Mod_Rev2.pdf

[EuroDat]

If you do decide to change the module to a HEI, you will need to design your own baseplate.

My drawing won't work on the E12-27. You will need to cut the connector pins off the board. Give yourself enough room to solder new wires to them. You will understand when you open it.

 

The baseplate will be held in place by the 6 pin connector. The connector will also serve as a spacer. The other side of the baseplate will mount on the original screw point and the back mouting point of the heat sink (with a spacer tube). Hope that makes sence. Should of made a drawing and photos when I made one for a 1978 280Z over here in January.

 

Chas

 

Edit: Found this photo on the net. It shows the way the connector is secured to the housing. The circuit board is mounted on the other side of the connector. The othe two screws you can see are the heat sink mounting screws.

Edited May 12, 2015 by EuroDat

[EuroDat]

Tomohawk,

 

Here is a link explaining the main differences in the HEI 4, 7 and 8 pin modules. http://www.megamanual.com/ms2/GM_7pinHEI.htm

 

The 7 and 8 basically have timing control features.

 

Chas

[TomoHawk]

Vielen Danke.  Wow, some of those HEI modules have "timing control."

Edited May 12, 2015 by TomoHawk