Hi gang,

Maybe y'all can help me figure out how to set up my IPD Weber DGV conversion kit with the engine's ventilation system.

I think '70 B20 didn't have a true PCV valve, but rather a flame trap above the block breather vent chamber which fed into the intake manifold via a small orrifice.

The DGV kit has a big port into the intake manifold just ahead of cylinder #2 intake. The oil fill cap is ported to the inside of the air filter just ahead of the DGV. I'm pretty sure this part is correct.

The way I got the car, the block vent was ported through a PCV valve into a T hose connector which branched to the brake vacuum booster and to the cyl #2 branch of the intake manifold. Car ran extremely rough like this and sure enough #2 spark plug was excessively white from lean condition. Blocking the line to the slightly leaky vacuum booster did not help. In spite of apparent constant vacuum to the block I had excessive oil running down the valve cover from the oil fill cap. Now I've got the #2 intake vacuum port completely plugged, the line from the PCV valve tie-wrapped next to the air filter, and a rag tied around the oil fill cap. It does run much better and smoother like its firing properly on all four.

I'm inclined to take the manifold off and drill and tap a port for the PCV into the bottom of the manifold directly under the DGV. That way the fumes from the crankcase and equivalent vacuum leak will be shared by all four cylinders instead of going only to #2.

Any suggestions? What should I procure as a PCV valve for in-line hose mounting? Should I install the Volvo flame arrestor right above the crankase breather?

Thanks in advance for any help or consolation !

Later,
Al