Which Coil?
 

I have a 71 Challenger, 440 Six Pack, Auto, Electronic Ignition. I have had issues with my coil. So I replaced it with a Accell 8140, now I'm told this is not the correct coil for the 440. Anyone know what would be the best coil to install?

"Blue Streak" HD! = 42,000 volts last time I had one checked!

8140 Comes up good on application on my end... As long as you followed the instructions !!! :)

"On paper" it looks like it should be OK what exactly are the "issues" you are having?

The biggest complaint: Hard Cold Starts. That said, a friend brought up the concern that the Accel 8140 has a built in resistor. Where the factory coil (2444242) is designed to be used with an external resister. Of course that got me thinking maybe the 8140 is not compatible, and the reason for the hard cold starts.

I have run both the accel and the Mopar race coils. They didn't last . Both fell down to under 23,000 volts in a single season of only track time. Both are JUNK offshore/Mexican product!

I was having the same problem as you and an erratic tachometer was the signal !

Do some googling and you will see many Blue Streak products on some good Hemi's!