I'm running a stock (Heavy Duty 12v) coil in my daily '73 Dart without ballast resistor.
If I reconnect the ballast resistor, the car starts to stumble at idle and die when put in Drive. I probably have the wrong resistor, but since I disconnected it everything still seems to work fine.
The coil's temp climbs right along with the engine intake's temp.

Today I decided to install a MSD Blaster 2 coil (also without ballast).
After starting the engine I let it run for a couple of minutes and used my infrared tempgauge and pointed it at the coil... It was already at 130-140F and climbing. I kept the engine idling for awhile to see where the temp would end up at and it went up to around 176F when I called it quits.

To me it's obvious the Blaster coil really needs a ballast resistor when used in a daily driver.


Has anyone ever measured the temp of a coil here?