1957 intake manifold pipe function

[TbirdFan76]

What is the function of the pipe coming out of the intake manifold behind the carburetor? I can't find information on this in my 1957 Ford Car & Thunderbird Shop Manual or online searches. Thrs pipe angles down towards the passenger side and is open at the bottom. Exhaust does exit from this pipe.

Please see attached photo for reference. Thanks!

 

[Birdman of coatesvile]

Older cars don’t have pcv- positive crankcase ventilation. So yours have a breather cap and blow by tub .leave it stock and enjoy the smell of that oil.

 

[cokefirst]

that is referred to as a "road Draft tube". The way it works is that the breather on the car (the cap for the oil filler tube) has a mesh material inside and is not sealed to the oil tube. The road draft tube has the end cut at an angle and it sticks below the engine. at speeds above 30 mph or so, the air passing the end of the road draft tube creates a vacuum that pulls the air in the engine along with the blow by gasses through the tube and out into the atmosphere. The air removed is replaced by air drawn into the engine through the breather cap.

 

[55birdman]

Are you old enough to remember when the highways had a dark line down the middle of each lane? This I suspect was from oil vapors being expelled by cars back then.

 

[Tom Alpers]

Are you old enough to remember when the highways had a dark line down the middle of each lane? This I suspect was from oil vapors being expelled by cars back then.

Some was probably from that, but I think most of it was because they all leaked oil, just like many of our y-blocks have a rear main seal leak that is so often seemingly impossible to fix. I was watching some old film from LA in the 40's and 50's where someone had put a camera on the back of a car and drove down roads all over LA. One thing that struck me was when you looked along the side of the road where people parked in front of their houses and businesses there was a large oil slick in just about every parking space.

 

[ICON 56]

That was the technology back then.

 

[Bruce Hardy]

I believe the intake pipe your speaking of will exit in a way that the choke housing pipe will screw down on it. In the choke housing itself should be a vacuum piston that helps open the choke, getting it's vacuum from port in the choke housing to carb. That airflow will then get heated from the intake manifold as the air passes from the intake end . This pipe can also rot out and start taking vacuum from the intake itself causing the engine to run like crap