I previously switched the points ignition on my 68 396 to HEI. Easy and straightforward. Now, I'm adding a Holley Sniper EFI, dual sync distributor, MSD 6AL, and MSD coil to the new 496 and I'm stuck on two things.
The american autowire engine harness I bought previously is modified for HEI by AA and has a dropout with a 12 GA pink circuit and 20 GA yellow circuit
terminated together in the connector (see pic) that plugs into the BATT side of the HEI distributor.
First issue, the yellow circuit. This is the coil-to-starter circuit on the OEM schematic and routes from the HEI plug to the starter on the AA harness. Nowhere in the holley EFI, dual sync, MSD 6AL, or MSD blaster coil is this circuit mentioned. The coil states specifically that only the circuits from the 6AL connect to its terminals. What do I do with this circuit?
Second issue, the pink circuit. This runs through the bulkhead connector on the frontwall and ties into the ignition switch. I suspect this is a switched ignition source. My issue is regarding the size of the circuit. The dual sync distributor requires a +12V switched ignition source, but it uses a much smaller 22 GA circuit. Can I splice this into the 12 GA pink from the harness or will I fry something? Do I need to replace the 12 GA pink all the way to the ignition switch with a matching smaller circuit? It seems like going from 12 to 22 GA would cause something to heat up that isn't supposed to.
There is a lot of info here, I know. Thanks for any replies
1968 Impala SS
Last edited by 68WASAGOODYEAR; 04-08-2019 at 07:35 PM.