Carbking, being technologically challenged I should have said 18" of vacuum. I was trying to write down his advice and hold a cell phone so I am sure I missed a lot of what he said. He was very accommodating since I purchased the Hei from him 10 years ago and he could me have sold me some unneeded parts. He even gave a cross-reference number for the vacuum advance that could be bought locally or from Amazon. BTW he sells the part.
MUCH more understandable than 18 degrees advance. Vacuum tests at different engine loads, along with compression and leak-down tests, are very good indicators of where to look for issues.
Again, good luck on your medical procedure, the truck will wait.
Jon.
