Anyone seen any issues out of these?

I’ve personally seen one MSD 7720 and heard of several that have failed. These can be repaired when sent back to MSD. My only 7720 over 10 yrs old has always worked. I believe the 7720 fails less than the 7730.

The temporary back-up to the 7720 that I carry as a spare is an older 6AL that has the correct mating Deutsch ends attached for quick install in the event of a failure. With the addition of the legacy cable and one parameter change in 7730 program the ignition is working properly.

The biggest problem I’ve seen multiple times with Grid installs, is that the Male Deutsch plugs with the Female pins, has pins not locked into position properly during assembly. Looking at the plate front (if there’s any assembly grease in the plate holes, blow this out with compressed air), the female pins should be tight against the back of the plate. If not, prying the flat plastic front plate off with a small screwdriver allows access to the pins that can be pulled into locking position and plate re-installed.

MSD 7720 has much power. NGK plugs with .030 gap new will have a .044+ gap after 500 runs in my engine. Still runs properly with wider gap. I have a new set of Autolites I want to try at next change.

I recently experienced a new MSD 7720 that a no start condition. There was a weak ignition spark when using my MSD Tester. The pins in the Deutsch connector were not properly locked into position so I thought that would fix the issue. It did not. So I installed another new MSD 7720 and that fixed the issue.

I had a 7al2 that went bad , and only symptom was the motor was a .10 slow out of nowhere until sent in for repair, was told it couldnt keep up keep up under a load. . Just curious if the 7720’s have done this.

Never happened?