Hi all, came across 2 pictures and would like to know the correct placement / routine of PCV or breather.

In the 1st picture the PCV is connected to carb and in the 2nd picture it's a breather connected to air cleaner assy.
The two pictures are from a 71 442 (not sure though). So what would be original if it's a 71 442 ?

Thanks

 

The second picture also has the valve covers installed incorrectly.
As for what's correct for a 1971 442, how about we go to the factory PIM instead of random photos on the interwebs? Note that on this drawing, the 664 engine is the Toronado. All others have the PCV on the driver side and the breather on the passenger side. If the clown who owns the car in the second photo had installed the valve covers correctly, that car would also have been correct. Also note that the car in your first photo has the incorrect PCV valve.

 

Thanks for the PIM page, now it's all clear in my head, so in the second picture of my 1st post, hope they didn't put a hole in that beautiful air cleaner base !!!!
Thanks again teacher !

 

They didn't. The factory MT cars used the "dual ventilation" configuration like the W30 cars. There were breathers in both valve covers and the PCV was connected to a barb on the intake. This is why the MT intake manifolds have a different part number than do the AT intakes. On AT cars, that hole on the driver side of the air cleaner came with a rubber plug.

 

Thanks for the correction, and this picture is what you explain, dual ventilation and the pcv on the intake right ?

 

Correct. Only used on W30s and 442s with manual transmission.

 

Thanks

 

Any particular reason Old engineers changed the PCV system for 442 manual & W30 cars?

 

That's a really good question that I haven't been able to find an answer to. The only thing that's remotely connected is that the W30s and MT cars had cams that generated less vacuum that did those in other engines, but the W31s never had this, so go figure. The 69 H/O was the first use of this setup and that 285/287 cam wasn't that radical either. It might be worth searching through SAE papers from that time period.

 

I think the thought process was that the W30 and manual trans cars would see more full open throttle which results in more crankcase fumes exiting backwards up the clean air side and towards the air filter. With 2 exits, the fumes would be more evenly distributed on the air cleaner element.