How to Upgrade to High Energy Ignition (HEI)

[stevedmc]

I'm just buying stuff to have on hand. HEI looks like a quick & easy upgrade I planned to do sometime in the future. When I asked if the flamethrower I planned to buy was the correct coil, Matt mentioned the ICM....I got confused and asked about it.

HEI is a pretty easy upgrade and your bosch ignition module is 110% compatible with it. Be careful listening to Matt. He is one of those EFI guys.

[Rich_NYS]

HEI is a pretty easy upgrade and your bosch ignition module is 110% compatible with it. Be careful listening to Matt. He is one of those EFI guys.

Thanks Steve, I think Matt is mentally abusing me....typical Thug forum behavior. Then Luke & Dave pile on me.... *sniff* I'll need some crayons after this.

I got my MSD wires today but put them on the shelf as fast as I could, I'm now somewhat afraid to open the box.....

[Boglin]

I've written it before, I'll write it again. The (dumb) Bosch ignition ECU expects the blue ignition coil to be connected to it. The blue coil has a high(er) resistance which takes a mathematically determinate amount of time to charge it. Therefore, for a given engine RPM, the Bosch ignition ECU will spend X amount of time charging the coil.

Then you swap that blue coil for a spicy-hot red one. The new coil is of a low(er) resistance and accordingly, charges more quickly. In fact, it charges so quickly that now the Bosch ignition ECU's predetermined charging routine is too long. Charging the coil more than necessary leads to excess heat. Excess heat leads to failure of the coil and/or ignition module.

I suggested the Pertronix D72000. You basically open the case for your old ignition module, rip out the guts, and install that module in its place, bolted to the aluminum casing with the supplied thermal grease. The Pertronix module has additional intelligence that allows it to determine when the coil is finished charging and stop; it's called "adaptive dwell." It knows when the glass is full. This prevents overheating the coil.

Now Steve has been using the Bosch ignition ECU with a performance coil for a long time and says he hasn't had any failures. I don't doubt Steve. Steve will freely admit when his vehicle burns to the ground. If Steve were SamHill-ing his DeLorean and using it as a grocery-getter, he may or may not one day find the ignition module and coil are toast.

[stevedmc]

Steve road around on that bosh module with a pertronix coil for at least a year before putting a ford module in the car.

I'll say this, I never leave the key in the run position unless the car is actually running.

I did that on my 65 Mustang once. I was listening to my tunes while wrenching on the car and then the coil went BOOM!!!!!

I'm not sure if that would happen with the bosch module but I'm not going to take any chances trying to find out.

What I'm doing works for me, but Matt is smarter than me. I'm just a monkey with a screw driver.

He's smart enough to monkey with electronics.

Sent from my SM-G900V using Tapatalk because I'm too lazy to turn off the mobile signature thingie on my phone.

[Bitsyncmaster]

Steve road around on that bosh module with a pertronix coil for at least a year before putting a ford module in the car.

I'll say this, I never leave the key in the run position unless the car is actually running.

I did that on my 65 Mustang once. I was listening to my tunes while wrenching on the car and then the coil went BOOM!!!!!

I'm not sure if that would happen with the bosch module but I'm not going to take any chances trying to find out.

What I'm doing works for me, but Matt is smarter than me. I'm just a monkey with a screw driver.

He's smart enough to monkey with electronics.

Sent from my SM-G900V using Tapatalk because I'm too lazy to turn off the mobile signature thingie on my phone.

The OEM Bosch ECU and the Ford unit Bill uses keep the coil powered with the key in the run position. Your resistors (if you have them),ECU and the coil will all produce heat (more so than with the engine running). I would not think it would blow up the coil but I guess you have found it can happen.

[Rich_NYS]

So when I swap out the coil & bypass the resistor[s] I just swap out an ignition module easy-peasy, right?

I'll look for a deal on one & put it on the shelf with the new coil.

You guys are killin' me.....Bill writes this thread over 3 years ago and nobody says jackshit about it until now.

[stevedmc]

The OEM Bosch ECU and the Ford unit Bill uses keep the coil powered with the key in the run position. Your resistors (if you have them),ECU and the coil will all produce heat (more so than with the engine running). I would not think it would blow up the coil but I guess you have found it can happen.

It happened on a 65 ford. I honestly can't remember if I was still running points or if I had upgraded to HEI or not. But it taught me a valuable lesson. Unless I'm in a fancy smancy modern car, I never leave the key in the run position unless the engine is actually running.

The OEM Bosch ECU and the Ford unit Bill uses keep the coil powered with the key in the run position. Your resistors (if you have them),ECU and the coil will all produce heat (more so than with the engine running). I would not think it would blow up the coil but I guess you have found it can happen.

Sent from my SM-G900V using Tapatalk because I'm too lazy to turn off the mobile signature thingie on my phone.