No PCV on a road draft system.
I'm inclined to think timing. Especially if you do not have a vacuum advance on the dizzy. I have also seen where with duals, there isn't enough vacuum at the carb base (ported vacuum) to make the advance work properly, so many go to the fitting on the mnaifold instead. On mine, I don't have an advance, so I had to advance the base timing by 15 degrees to get it to run properly.
