The coil will live at almost any voltage you want to throw at it.
It's the module power switching transistors that take the beating.
I haven't used a resistor in 20 years using the DuraSpark module, but if you want to be safe, use a resistor.
My best friend has had his vintage Mustang (daily driver) running for 10 years using the same module, and no resistor.
I use the E-core coil with no resistor.
The factory guys say 1.35 Ohms total resistor to keep the module alive, but they use a 1.35 Ohms resistor alone, not to mention the resistance in the coil (around an extra .45 Ohm)...
TR, I'd like your recommendation on coils. Which MSD coil or other would be the best to use with the MSD 6a? This is for an AMC 360 that is driven almost every day. Here's some pictures of how it looks now with the exception of the addition of an accel foam filter last night. Currently I have the cheap coil for Ford applications.
What are you asking me for, you have the answer bolted to your compressor.
That E-core and the Premium canister coils will both do about the same when attached to a MSD 6 series module.
The advantage of the E-core coil is the high voltage terminal configuration, NOT being oil filled you can mount it at any angle, and you can replace it at any auto parts store or junk yard on the road.
No problem man.
I have no problems with the current coil, I was just wondering if there was a better coil. Most of the time price reflects quality. I didn't know if that was the case here or not. In a summit catalog, for example, there are a number of e-core coils from MSD, ACCEL, Holley and Crane which are in the $35-$50 range. The one I have was about $15. Again, thanks.
I've seen the $100+ MSD e core's used and they don't produce any appreciable improvement for our applications, and I can afford to have 2 extra spares for the same price. They're also easier to find on the shelves in local shops.
'83 CJ-7 nothing original but the tub and axle tubes