Timed VS manifold Vacuum Port

[pkjorlie]

What is the difference between timed vacuum and manifold vacuum ports on my Edelbrock 1405 carb? I haven't gone to my storage place to look if I have my Distributor connected to the manifold vac port or the timed port. The manual, now that I've read it, says to connect to manifold vacuum port if no emmission controls are used. I don't have any emmission controls or smog pump on it (Shhh).

I do know I've been getting lousy gas mileage (about 10 mpg) on my BII. It may be that my vacuum modulator is connected to the timed port and it isn't shifting into 3rd? (i don't have a taco-meter either)

[plowboy34]

manifold vacuum will have vacuum at idle and timed vacuum will not have vacuum at idle. You want the modulator hooked to manifold vacuum and your distributor hooked to timed vacuum. The best way to tell if a port is timed or manifold is it's location compared to your throttle plates. If it's below the throttle plates it is manifold and above plates is timed.

[pkjorlie]

Even though Edelbrock recommends using Manifold Vacuum for Dist Advance when emission controls are not used?

[pkjorlie]

I went down and looked. The timed Vac port is connected to the distributor. The Manifold vac port on the carb is connected to the Fuel pressure regulator, the vac port at the rear of the carb for power brakes is connected to the transmission modulator, and the port on the manifold itself is connected to the power brakes.

[Dave]

Hey old buddy! Found a lot of conflicting info on the net, sure you did also.
http://www.allfordmustangs.com/forums/c ... 289-a.html

How about posting up some pictures of that BII, think it's the only one on here. Tapping them trees like crazy now?
Mac