Posts: 1
Threads: 1
Joined: Sep 2011
My 73 with 351C 2v has a vacuum port on the spacer block between the engine block and the carb. I discovered it after cleaning my engine and it quit running at all. Apparently it was plugged and I knocked the plug off. I plugged the port and it runs fine now. Anyone know what actually goes there? Thanks!
Posts: 350
Threads: 21
Joined: Jun 2011
I believe it is where the passengers side PCV hose that comes off of that passengers side valve cover connects to.
I just did a check and according to a discussion on allfordmustangs.com I stole a quote from a mechanic that states the following:
"Use the port on the carb.
The intake manifold fitting is for automatic transmission vacuum modulator and brake booster connections, not PCV. Cap it if you do not have a use for it. A PCV system has constant airflow through it, unlike vacuum hoses for brake boosters and transmission modulators, and should never be connected to an intake runner. It will lean out one cylinder if you do."
You should do some more verification on this one.
Evidently I was wrong when I stated that it was for the PCV connection.
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