I was running a complete MSD system with the Pro Billet Distributor also and sure didn’t wanna mess around removing that, but after talking to a couple guys that kept preaching to try the Vacuum Advance and literally trying everything else with no luck whatsoever, including gaping the water pump, I ended up getting desperate and removed the MSD setup and picked up a HEI, and it was by far and away the greatest thing I ever did to that car. Like I mentioned previously, I played around with a few different advance cans before settling on one and I can tell ya, I wouldn’t be afraid to go in a parade on a scorching hot day now!! If and when you run outa other options, I highly recommend trying this!! I feel like the car car even runs a bit cleaner/crisper with that HEI/Vacuum Advance Setup and looks cleaner under the hood.
