Reply to "How to do the ignition timing on a mangusta"

Neither the Ford 427, or the Ford 289hp engines, 63-67, use vacuum advance distributors. They are strictly mechanical advance distributors.

They were dual point distributors which was done to increase the available dwell.

They were designed for real high performance, which in those days meant racing. They were perfectly at home street driving or racing. They are very versatile devices. Generally well built with few problems.

The vacuum advance distributor CAN give you 2 more MPG,which is what it was initially intended to do, but the drawback is that at high RPM, they tend to be erratic and cause inconsistent timing starting around 6,000 engine rpm, sometimes lower.

Because of the initial struggle to deal with exhaust emmissions inexpensively as possible, the auto manufacturers found the vacuum modification of the advance/retard of timing in the distributor helpful.

If you are going to run an engine hard for maximum performance (over 6,000rpm) you really do not want a vacuum advance distributor at all.

The debate over ported or engine vacuum becomes a technicality along with the "how many Angels can sit on top of a pin" discussion?