Ignition module reliability GM HEI vs Ford TFI-IV

[brianl703]

It was already installed in the new/rebuilt distributor.

Who knows what kind of grease they used?

 

[Blackstack]

Who knows what kind of grease they used?

Yup. I recall some of the others possibly coming with clear grease? Second guess everything I guess.

 

[brianl703]

Yup. I recall some of the others possibly coming with clear grease? Second guess everything I guess.

I ordered some of this. Going to remove the HEI module and re-grease it. Seems like that might be good preventative maintenance.

Polysynthetic silver thermal compound paste maximizes thermal conductivity between the CPU and heat sink/fan assembly.
Weight: 1.0g/tube
Operation Temperature: -50/280°c
Thermal Conductivity: >3.17W/m.k, Thermal Resistance: w
20% metal oxide compounds

 

[OVERKILL]

Ford moved the TFI module from the distributor to the inner fender after a while and apparently that helped, but a smart fellow keeps a spare in the glove box. It is apparently impossible to buy a quality replacement module these days.

Yes, I had a spare OE module because they were MUCH better quality, but quite hard to find. I never had one fail after doing the Arctic Silver trick though, didn't even remotely mount it (though you could).

 

[ripcord]

Hopefully that holds true for the one gasser OBS Ford left in my stable, as I used CPU cooler compound as well when I replaced the module several years ago.

The module that has surprised me the most by not dying is the 45 year old Duraspark II box in my '50 Chevy. Half of the potting material melted out over the years but it just keeps working.

 

[paulo57509]

I used Arctic MX-4 when I re-assembled the Safari's brake control module (reflowed fractured solder joints).

 

[nthach]

The Japanese mounted theirs inside the dist on most models...trying to dump current into a dist body already running at engine temp was a recipe for failure. The Euros mounted them externally, and they lasted forever.

The Toyota/Denso IIA and Honda’s version of that on their I4s, while the 6/8 cylinder cars got their igniters mounted with or near the coil. The external Denso igniters on Toyotas never usually fail.

 

[hank2]

I did a GM HEI module conversion 4 years ago on my '82 slant 6 Dodge truck. Very common conversion on late 70's and 80's slant 6 with lean burn ignition. I used the specified 4 pin GM module that Chevy used on some vehicles from '74 to sometime in the 80's. (Like the 1977 Chevette). My Delphi DS10071 module is still doing fine. I have one or two supposedly real USA GM units but haven't needed them yet.

They usually come with paste, but I used the good silver thermal paste mounted on a GM heat sink on the fender. Many of the cheaper modules you see on ebay or Amazon have very bad reps.