Why HEI Mod?

[Maliceday]

So, can someone please explain what exactly the HEI swap does? From everything I've read up on I'm assuming better spark, but that's the best I can get out of it. Also, is this on all engines or only select ones?

[Ryan]

I'm feeling nice.

HEI mod is the 'fix' for the poorly designed ignitors in these cars. It only fixes the ignitor, not the coil. that is what the external coil add-on is for.

ignitor failure reveals itself as misfires at certain RPM's, motor dying when hot, not restarting when hot, running fine when cold, eventually moving to no spark.

[Maliceday]

Awesome. Thank you. I've been trying to find out exactly what it's for though all the writing I could find on it.

[Rick Johnson]

I'm feeling nice.

HEI mod is the 'fix' for the poorly designed ignitors in these cars. It only fixes the ignitor, not the coil. that is what the external coil add-on is for.

ignitor failure reveals itself as misfires at certain RPM's, motor dying when hot, not restarting when hot, running fine when cold, eventually moving to no spark.

Good post, just like to add. Most people end up doing the mod after they have an igniter failure, which to fix requires a whole new distributor - if you want a good laugh call mazda and ask what the cost is ~$500. You can get the GM igniters for $0-$5 at a wrecker and are found in a ton of vehicles - I used to keep a couple spares in the glovebox just in case.

[Daninski]

Just in case you didn't see this. http://www.mx-3.com/phpBB3/viewtopic.php?f=23&t=69006" onclick="window.open(this.href);return false;

[Ryan]

You can actually replace just the ignitor, Mazda used to do that for people, but they quit making just spare ignitors.

I still buy distributors from yards, pull the coil and ignitor, test them, and keep them if good, fill the disty with crap stuff, and then return it


HEI looks messy, unless you take a lot of time to do it.

[hgallegos915]

I had a horrible experience... maybe it was my car, wiring.. something...

But My ignitor went out a looooong time ago, so i bought a shiny new disty for 300 dllrs at checker autoparts(now o relleys). I had it on, lasted 3 days, BOOM ignitor went... I got a replacement under warranty.. boom 1 day later... I went back and they replaced last time and said they wont replace again as its my car.. well yeah it went again a week later... so I got fed up.. did the hei mod and it worked.. I could have freaking done that with the first disty.. The ignitor lasted me 6 months, went out due to poor ground. Got it corrected and replaced and its been well for 3 years.

Also autozone sells the internal coil so no need to do external coil mod unless you want it. its like 50 dllrs for the replacement coil at autozone. Seen it for 40 dllrs online.