68 Polara HEI Conversion

[GMPolara]

I just got finished with an HEI Conversion on my 68 Polara, 383CID. At least I thought I was done. It's been burning HEI modules one after the other. I've checked for a good ground, made sure to mount with the proper heat sink and used the correct paste under the module. Also, I bought a rebuilt disty for a new mopar, a 73 Newport. Here's a link to it:
More Information for CARDONE 843897

Any ideas on what could be causing this?
Here's the diagram that I used to do this conversion:

Also, here's a link to a video showing my new system:

 

[CBODY67]

The GM HEI modules are very reliable, at least the ones from GM are, from my experience.

Is the module grounded into the dist housing? Which means the mounting flange where it mates to the block of the engine. Which then needs to be grounded to the chassis. Or you might run a direct wire from that mounting screw to the block itself.

Cardone might be the dominant player in the modern reman parts arena, BUT that does not mean they are the best choice, as others in here have noted on their other reman parts, over the years. FWIW So be prepared in case one part of the electronics might fail sooner than later.

Look at the Cardone part numbers in Rock Auto, then look at what NAPA sells. Same number, just a different location for the "-" in the part number. NAPA might cost a bit more, but they also have somebody local to you that your can look in the eye should something fail.

The other thing about their reman distributors is the advance curve. Look at all of the lines of Chrysler part numbers their ONE distributor replaces! That means one of two things . . . you are getting a generic advance curve and vac can calibration or you are getting the advance curve of the distributor that was reman'd. In either case, not the one your engine came with from Chrysler. Which means you might want to check the advance curve to see what you have, especially how that might relate to initial base timing settings.

ONE OTHER THING, by the time that HEIs were OEM on GM engines, they had also gone to electronic voltage regulators, which Chrysler didn't do until they started to use OEM electronic ignition in the early 1970s.

Perhaps you need an OEM-style electronic voltage regulator. One of the members in here sells them on eBay. Might need to upgrade.

Just some thoughts,
CBODY67

 

[Big_John]

ONE OTHER THING, by the time that HEIs were OEM on GM engines, they had also gone to electronic voltage regulators, which Chrysler didn't do until they started to use OEM electronic ignition in the early 1970s.

Perhaps you need an OEM-style electronic voltage regulator. One of the members in here sells them on eBay. Might need to upgrade.

This is a great suggestion and possibly contributing to the problem, if you have an OEM type mechanical regulator. Most electronics are fussy about having a steady current flow. The mechanical regulator works by points opening and closing rapidly to maintain an average voltage. Electronic regulators actually do the same, except it's so much faster that the current is much steadier.

Have you bypassed the ballast resistor? Again, electronics want a solid 12-14 volts. Also, what about the coil? I think you want a coil with 1 to 1.5 ohms primary resistance. A lot of guys are running a Ford E-core type coil.

BTW, IMHO, I'm not a fan of having that coil mounted on the fender well as they did in the video. I think the strain of vibration and movement of the coil wire is worse than heat from the engine on the coil.

 

[Snotty]

I agree with Big John, did you bypass the resistor?

 

[GMPolara]

Whoops, i probably should have included more detail. I have bypassed the resistor. The ICM is grounded to a common ground on the firewall. This does have a wire connected to the back of the intake. Also. I'm using a Pertonix, Flamethrower 3. It has a very low resistance, 0.32 ohms.
The voltage regulator was upgraded to a 60amp unit. I'm not sure if it is electronic. Here's a link to what I bought. If it's not electronic then please leave a recommendation for one.
https://www.oreillyauto.com/detail/...n-12-volt-15-amp-voltage-regulator/std0/vr106

I am a bit concerned that the ignitor isn't compatible with the coil. The instructions called for a special Pertonix ignitor. I dismissed it a sales hook. Might need to reconsider.

 

[Big_John]

Whoops, i probably should have included more detail. I have bypassed the resistor. The ICM is grounded to a common ground on the firewall. This does have a wire connected to the back of the intake. Also. I'm using a Pertonix, Flamethrower 3. It has a very low resistance, 0.32 ohms.
The voltage regulator was upgraded to a 60amp unit. I'm not sure if it is electronic. Here's a link to what I bought. If it's not electronic then please leave a recommendation for one.
https://www.oreillyauto.com/detail/...n-12-volt-15-amp-voltage-regulator/std0/vr106

I am a bit concerned that the ignitor isn't compatible with the coil. The instructions called for a special Pertonix ignitor. I dismissed it a sales hook. Might need to reconsider.

I looked at the voltage regulator and it seems to say it's electronic, but it really doesn't confirm it. More Information for STANDARD MOTOR PRODUCTS VR106 I looked at the Standard Ignition website and nothing positive there either. Best way to see 100% would be to pull the cover. 2 screws and you'll see what's in there.

It's a topic for another discussion, but your 60 amp alternator won't use a 60 amp regulator. All the regulator does is switch the alternator field off and on. It does not carry that 60 amp current through it. The electronic unit does smooth the switching out, therefore giving you a more constant output.

Regarding the coil. I can't find another source other than this for primary resistance and they say 1-1.5 ohms. Mopar HEI Conversion

 

[MoPar~Man]

Burning Out Chevy Hei Distributor Ignition Modules

bad engine grounds or ,high resistance electrical connections, like coil wires, or a defective coil, and worn ignition wires, bad, battery and engine electrical connections and faulty grounds are primary sources for this problem, the more ohms resistance, in the ignition, system's wiring...

garage.grumpysperformance.com

 

[GMPolara]

I looked at the voltage regulator and it seems to say it's electronic, but it really doesn't confirm it. More Information for STANDARD MOTOR PRODUCTS VR106 I looked at the Standard Ignition website and nothing positive there either. Best way to see 100% would be to pull the cover. 2 screws and you'll see what's in there.

It's a topic for another discussion, but your 60 amp alternator won't use a 60 amp regulator. All the regulator does is switch the alternator field off and on. It does not carry that 60 amp current through it. The electronic unit does smooth the switching out, therefore giving you a more constant output.

Regarding the coil. I can't find another source other than this for primary resistance and they say 1-1.5 ohms. Mopar HEI Conversion

I'll check on that tomorrow. In the mean time I'm going to buy an E-core coil. It's easy enough to remove the coil from the equation. Thx!

 

[GMPolara]

This is a great suggestion and possibly contributing to the problem, if you have an OEM type mechanical regulator. Most electronics are fussy about having a steady current flow. The mechanical regulator works by points opening and closing rapidly to maintain an average voltage. Electronic regulators actually do the same, except it's so much faster that the current is much steadier.

Have you bypassed the ballast resistor? Again, electronics want a solid 12-14 volts. Also, what about the coil? I think you want a coil with 1 to 1.5 ohms primary resistance. A lot of guys are running a Ford E-core type coil.

BTW, IMHO, I'm not a fan of having that coil mounted on the fender well as they did in the video. I think the strain of vibration and movement of the coil wire is worse than heat from the engine on the coil.

Looks like my Regulator is point type (see pic). So now I'm on the market for an electric regulator. Any recommendations?

 

[mgm1986]

I tried parts store electronic regulators on my '68 Fury and after three failed attempts I converted to a GM 1-wire alternator which has the VR built in. One heavy gauge wire from the alternator to the battery. It worked very well.

I did the same on my '68 300, replaced with a 1-wire alt, and it too works really well with the GM HEI module.

I did try converting the Mopar alternator to a "1-wire" by adding an external VR but it actually was overcharging and I could not get it down to an acceptable voltage so I put the original alternator on the shelf.

Seeing that you already went with GM HEI it seems this could be a good alternative solution. Good luck with whatever you choose.

 

[Big_John]

Looks like my Regulator is point type (see pic). So now I'm on the market for an electric regulator. Any recommendations?

View attachment 662127

@FURYGT sells electronic regulators and everyone seems to be happy with them.

 

[live4theking]

@FURYGT has quality regulators.

 

[GMPolara]

I tried parts store electronic regulators on my '68 Fury and after three failed attempts I converted to a GM 1-wire alternator which has the VR built in. One heavy gauge wire from the alternator to the battery. It worked very well.

I did the same on my '68 300, replaced with a 1-wire alt, and it too works really well with the GM HEI module.

I did try converting the Mopar alternator to a "1-wire" by adding an external VR but it actually was overcharging and I could not get it down to an acceptable voltage so I put the original alternator on the shelf.

Seeing that you already went with GM HEI it seems this could be a good alternative solution. Good luck with whatever you choose.

Was the Regulator causing you to burn up HEI modules?

 

[mgm1986]

Good question, I don't know. On my Fury I did not convert to HEI. On the Chrysler I converted to HEI and the GM alternator at the same time and haven't driven more than a few hundred miles.

If you can convert to a solid state electronic VR or go with the GM alternator with one built in, it's definitely going to provide a more consistent voltage compared to a mechanical VR. As @Big_John mentioned, electronicals don't love fluctuations in voltage. That's where I would start and there are also other benefits that go along with replacing the mechanical VR.

 

[mgm1986]

Also, what voltage is your mechanical VR putting out when running at idle? At cruise speed? Over voltage could definitely be problematic.