So confused as to why front bank not smoothly running solo?

my 308 2V is running rough an backfiring. when I disconnect the main ignition wire to the front bank and the rear 4 cylinders run like they should. I reconnect the fron and the engine runs worse, I disconnect the rear Bank main wire and it seems the front bank only running on two cylinders.

Maybe I dont have the cam timing correct as tried to re-correct a poor cam timing job.

what I did before is line up the cam shaft timing notches (on the exterior part of the shaft) to the top of where the center of the cam cap would be.

the rear two aligns at the PM1-4 on on the flywheel, then set to PM5-8 for the front bank.
and align the two notches on the front cam shafts.

Ive read contradicting info that says all 4 shafts should line up on the PM1-4 mark on the fly wheel.
which is correct?

thanks for you help.

 

Thanks Steve for your quick reply!