HEI & Blaster 2

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67dartgtgo

67dartgtgo

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Has anyone used a Blaster2 coil, resisted or unresisted, with an HEI module conversion.
I picked up a disguised mopar ECU/HEI conversion and have a Blaster2 coil but no E-coil and was wondering if I could use the Blaster2 coil unresisted and not burn it up.
 
Greg and I talked about it some and we're not quite sure but I thought I'd throw out the fishing line and see if anyones done it yet.
 
TrailBeast said:
My suggestion was to find out if the coil is internally resisted or not.
Click to expand...

I don't think they are. But I could be wrong. I do know if you run a Blaster 2 they still require the ballast, just a different one over original.
 
From what I can decipher, it will work with an HEI and full 12+ volts (probably lots better than stock mopar ecu and coil with ballast) but it is not optimal compared to a proper E core designed for that era HEI module.

The HEI module will start clipping current at a lower number (sooner) when it has a higher ohms coil hooked to it. This makes the Blaster II coil less optimal than the correct E core.


It looks like the Blaster II unit can run at full 12v. It has .7 ohms with out the external ballast hooked up.

http://apps.msdignition.com/coil_blaster_1_8200_8202_8223.htm


Optimal ohms for a GM HEI is about .45 - .5 from what I have read.
 
Since you have the Blaster II, I would run it at 12 volts. I am quite sure it will do a great job of lighting the fire. Many people run the HEI with a blaster II. Not sure if they run the external .5 ohm ballast but I would not.
 
Rice Nuker said:
It looks like the Blaster II unit can run at full 12v. It has .7 ohms with out the external ballast hooked up.
Click to expand...

On electronic ignition it can. Points needs the ballast. I have always argued the fact that the ballast was to protect the coil and have been told I'm wrong. The ballast was originally used to help points last longer, not protect the coil.
 
Gotcha....going to run it ...without ballast....see what happens.
 
67dartgtgo said:
Has anyone used a Blaster2 coil, resisted or unresisted, with an HEI module conversion.
I picked up a disguised mopar ECU/HEI conversion and have a Blaster2 coil but no E-coil and was wondering if I could use the Blaster2 coil unresisted and not burn it up.
Click to expand...


I've run the HEI both ways, 66 cuda with the MSD ballast, and 73 Duster without. Either works fine, and long lived.
 
The HEI has a built in current limit and dwell control. Inquiring people like me place a 0.1 Ohm non-inductive shunt in series, and measure the current using Ohms law and a scope. The current will ramp up, then flat top when limit is reached. Typically current limits are set to 4-7A. Many coils will start to fail at 5A continuous with long term use, but at higher RPM, the average current is less.

Spark energy increases by, current squared, times coil primary inductance.

At higher RPM the charge time is insufficient for single coil systems, so the current limit is often not a consideration above 4000 RPM.

Picture shows current limit of 5.4A. This is from an ignition I made, not HEI, but result would be similar.
 

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KitCarlson said:
The HEI has a built in current limit and dwell control. Inquiring people like me place a 0.1 Ohm non-inductive shunt in series, and measure the current using Ohms law and a scope. The current will ramp up, then flat top when limit is reached. Typically current limits are set to 4-7A. Many coils will start to fail at 5A continuous with long term use, but at higher RPM, the average current is less.

Spark energy increases by, current squared, times coil primary inductance.

At higher RPM the charge time is insufficient for single coil systems, so the current limit is often not a consideration above 4000 RPM.

Picture shows current limit of 5.4A. This is from an ignition I made, not HEI, but result would be similar.
Click to expand...

OHHHH, well thanks for clearing that up for us. :D

Seriously though, thanks for helping answer the questions guy's, as I had stuff I had to go do and couldn't do the investigation of the details at the time.

Thank you all.
 
I'll 3rd the "no ballast needed", and that will give a stronger spark. The HEI module limits the heat in the coil, as KitCarlson shows, and much more effectively than a ballast does. Look at the ready-to-run HEI distributor on ebay by SteveWhitePerformance (or such). He says you can run the factory coil without a ballast, and you can get an even stronger spark if you use an e-core coil.
 
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