Ferrari 308GTS Ignition woes. Tracing an intermittent fault pt6

Warm and about 10 miles in, the car backfired and lost power. Naturally I put this down to carburation following the rebuild, but a quick test showed no power reaching the plugs on the rear bank. Therefore ignition issues!
New coils and ignition modules ordered, but not necessarily the right move.
Hella amplifier, particularly part number 5DA 006 623-051 boxed HELLA GmbH & Co. KGaA appear to have a bad batch with others experiencing difficulties. The result was the car ran, but couldn't rev.
Coils from Pertronix have a higher internal resistance to the original meaning a slower recharge, but given there are one per bank, this shouldn't be an issue if mated with a Pertronix amplifier. More investigation required to confirm.
However, I ended up cleaning and refitting the original equipment and after repairing a broken earth strap, may have resolved the issue.
Enjoy the video
Please remember, I am not a trained mechanic and what I do may not be the best / correct way but works for me. Videos are made as a guide of how I do / did it rather than a bible for others to follow.
Thanks for watching.

[@d.s.v.6404]

Great video! I’ve followed your channel, and I’m also an FChatter (Dane). I rebuilt my carburetors as well, but that didn’t completely remedy my issues so I replaced the coil (single points distributor) with an MSD High Vibration coil. I replaced the plugs and installed new wires (Accel 4040). I can’t say exactly what cured my problems, but she runs fine now. Thanks for sharing your work! 1978 GTS 25349

[@workinprogress1098]

Thanks for getting in touch. There is something quite satisfying about rectifying an issue. Even if, as a novice, you go about the long way. 🤣

[@nutzediezeit]

Super useful, thanks 😊

[@workinprogress1098]

You're welcome 😊

[@alexjenner1108]

Many Italian cars had a similar ignition system. My 1982 Alfasud Ti used Marelli AEI 200B instead of the Marelli AEI 200A on your 308GTS and my coil measures about 0.8 ohms. Those ignition modules, that you replaced with Hella, perform several functions, including dwell angle control and current limiting to around 5.5 - 6 Amps. Changing to 1.5 ohm coils shouldn't make too much difference at low to medium rpm, but might limit performance at high rpm. Most likely cleaning up all the connectors, replacing old heat sink compound and fixing that dodgy earth was all that was needed.

[@workinprogress1098]

Fingers crossed Alex. So far, so good, but the warmer weather will tell. 🤞🏼