I have an A14 from a B210. Because of size constraints I've removed the air cleaner and substituted one from a VW. I'm wondering what I should do with the PCV line from the top of the valve cover. It used to terminate at the air cleaner housing, but outside the air cleaner (so not much vacuum.) I'm tempted to hook it to the line that supplied the power brake servo: loads of vacuum. Are there any obvious problems with that?
Thanks for any suggestions.

Yer that's a problem.

The top hose is an air breather hose. So either attach it to the air filter, or separate air filter, or just leave it open to the air.




The main problem with leaving it open to the atmosphere is that nasty-smelling fumes will get in the passenger cabin occasionally.

In order to retain the anti-backfire protection, leave the original hose connected to the rocker cover, but you don't have to connect it to any air cleaner.

Of course that method will convert it partial positive ventilation. It'll work as normal at idle & low throttle, but will only passively vent at higher throttles (because there is no vacuum at higher throttle -- not even at the brake hose).

To retain the positive ventilation:
* Drill a hole in the VW air cleaner
* Buy a hose adapter at your local auto parts store
Like this white angle adapter included in the Weber 32/36 kits

Excellent. I had to build a different bottom adapter plate so I could mount the temp sensor and vacuum references for a couple other things, so I already have a port that'd match the PCV. I may have to scrabble together an anti-backfire valve, but that shouldn't be a problem. Thanks!

Sounds good!

No need for a complicated anti-backfire valve as in an EGR system. The factory hose just has a simple baffle in in, which Datsun calls a "flame arrestor".

I'm tempted to use a bit of mesh and some copper wool to emulate that flame arrestor. Thanks!