Regarding the ignition, I had originally bought one of the ready to run distributors from 440Source(yes, poor choice). Well it didn't work, so a few weeks ago installed a Proform 440-428 unit. Works great. No issues. Here's my question, and forgive my ignorance. The engine builder told me to never hook up the vacuum advance on the distributor. Plug it and leave it. When I asked him why, he said it would pull 55 degrees and the motor would detonate big time. Can someone please explain why this would happen? Everyone who has looked at the car or worked on the car has asked why I haven't hooked up the vacuum advance. The initial timing is set at 15-17, and the total is set at 36. Automotive electrical is a huge weak spot for me, and I literally need someone to explain. Thanks for any and all responses.