Re: Desmogging a 240z: I’ve studied this carefully and consulted (real) experts for confirmation, and here’s what I’m going to do to my stock ‘72 240z: Replace stock air filter with K&Ns, Remove Air pump and connected hoses, remove check valve on air galley (on exhaust manifold) and plug with threaded hex bolt, remove anti-backfire valve (aka flame trap), cap connection to balance tube downstream from AB valve, plug vacuum leading from AB valve to balance tube, Connect orphaned vacuum tube coming from flow guide valve to the closest carburator-to-air filter vacuum line using T connector. Remove crankcase cover hose that went to stock air filter and replace with K&N valve cover air filter. Whew!
Ive decided to retain the hose from crankcase to the balance tube/PCV valve.
Let me know your thoughts - very open to further coaching!
I’ll post further if everything does NOT go well. Otherwise, assume this works!
Jughead