Hello, I have a question related to manifold vs. ported vacuum for the vacuum advance. I know it's not directly related to this thread. But I have a 67 R/T with a 440 that has a Speed Pro cam that's 300/300 at the seat 230/230@.050, 109 LSA and .480 lift. With the vacuum advance hooked to the ported connection(factory) port on the carb the idle is somewhat choppy. I was advised to connect the vacuum advance to manifold vacuum, which I did and this really cleaned up the idle. I almost forgot to mention that I have a six pack setup on the car as well. Does anyone see a problem with using the manifold vacuum for the vacuum advance with this setup? Thanks everyone!