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What in crazy auto zone upgrades is this?

What you're seeing is most likely 1 of 2 things.

A B20 installed in a pre-PCV equipped 122 or a B20 installed in a 122 that had PCV, but is now using a pre-PCV intake manifold.

Prior to 1965 models, PCV wasn't required and the B16 and the early B18 engines came with road tubes for the block and an oil filler cap that didn't have a hose barb.

AFAIK, Volvo never offered a road tube for the B20.

We would normally install the later aluminum dual SU intake manifold that has the PCV vacuum port in the middle of the balance tube which would then be fitted with the correct ported B20 PCV fitting and a length of the correct size and style of oil resistant PCV hose and connect it to the breather box making sure the flame trap in the breather box is intact.

There's nothing wrong with leaving the air filter on the oil filler cap. If wanted, a proper breather hose can be used, but this would require the correct front air filter set up to accept the other end of the breather hose.
 
Technically, no, the engine should run just fine without a PCV system for normal driving. It would be better with a road tube with the end of the tube extending below the engine which exposes the end to the air stream under the car which helps draw out the block gases while moving, but there are 2 advantages to PCV.

For performance, PCV does a better job of removing the block gases that can restrict the movement of the rotating assembly inside the block and the PCV gases are combusted and that helps keep the air we breath a little cleaner.

I want to add that there is an alternate hose routing for the PCV system for a B20.

The hose connected to the oil filler cap can be connected to the PCV vacuum fitting at the intake manifold and the hose from the breather box would then be connected to the front air filter or an air filter can be mounted directly to the breather box. This was the early routing Volvo used, but later used the previously mentioned hose routing.
 
68;

Good info from Eric (Planetman)!

With those tiny air filter on both ends of the Crankcase, and no extraction of PCV gasses into the intake, PCV has essentially been made into a OCV (Open Crankcase Ventilation)! Functionally, there is nothing wrong with it...some creative PO "replumbings" (like this: https://www.sw-em.com/pcv_diagrams_and_notes.htm#Creative_(but_wrong!)_PCV_Plumbing ) allow Crankcase pressure to build up, causing oil weepage, and that's very wrong...

Cheers

C1800; Thanks for reference!
 
'68;

Don't let the connection of Brake Assist Unit to intake Vac confuse you...it obviously also needs Vac, and directly, so often, with the presence of a BAU PLUS PCV (not uncommon!) you will see some sort of combination of the plumbing...the important thing is that Vac is direct to BAU unit (with a check valve either internal to BAU or external), and PCV is by way of a oil compatible hose, flame-trap PCV Valve and orifice to prevent a backfire (flamefront in manifold) from making its way into CrankCase.

Sometimes, as with engines which are long in the tooth and have significant blow-by, the flow of CC gases overwhelms the PCV sys, so flow direction is towards Air Filter, and oil-laden gases make their way to the AF and glob it up...Carb doesn't breathe so good after that!...that's when the line is removed from AF to prevent this from happening again, and the little AFs are installed to provide fresh filtered air to the CC...

As long as all of the simple requirements are met, many roads lead to Rome!

...and thanks for the kind words!

Cheers
 
1968 volvo said:
How about the valve cover? I think its just pretty looking.
Click to expand...

It's pretty, it's aluminum as opposed to the flimsy steel ones from the factory so you should have fewer leaks from the top of the engine and it gives you more clearance when you have a hopped up engine with aftermarket lifters for example.

Is it truly a necessity ? Nope. They sell for $150-$250 depending on whether they are painted or powdercoated, have the Volvo lettering, etc...
 
Keep an eye on the steering coupler. From my experience and VW days, the polyurethane gets brittle and cracks. I've seen them fail and it's a scary experience. The stock ones sold by VP and others is a much safer option, IMHO.
 
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