Quote:
Originally Posted by DanEC
The full time vacuum source you should hook to your distributor is under the front bowl, coming out at an angle and currently capped.
|
Agreed - in the photo you can see the end of the black cap sticking out a bit from under the primary fuel bowl - that's a manifold vacuum port. Just remove that black cap and connect the vacuum line which is currently connected to the timed / ported vacuum fitting on the side of the metering block. Don't forget to cap the timed / ported vacuum fitting on the carb that the vacuum hose is currently connected to. I believe both ports take 3/16" hose.
You'll find the idle speed will go up and the idle will most likely be a bit smoother after switching from ported / timed vacuum to manifold vacuum.
I used manifold vacuum for my connection and had to adjust the idle speed screws to drop the idle by about 200 RPM after I made the switch. Make sure the engine is fully warmed up and off fast idle before you make any idle speed and/or mixture adjustments.
Quote:
Originally Posted by DanEC
Not completely sure but I think the upper port on the right front side of the carburetor and fuel bowl is a ported vacuum source.
|
I checked a Holley diagram and confirmed the upper port on the primary metering block is a timed / ported vacuum source.