OK, so I understand that with emissions in mind that any gasses from worn rings etc. are oily so they want them to go into the combustion chambers and get burned.
And I can see that the inlet manifold is a source of "suck" to pull the gasses out of the rocker box and into the chambers, but.... what does it do to the mixture that the carburettor has just carefully made perfect?
Surely allowing unmetered, poorly mixed, probably not all vaporised, air and oil direct into the inlet manifold must do bad things to the vaporised fuel mix and therefore engine performance???
Surely it would be less damaging if it went into the air intake of the carburettor?
Why do we need "positive crankcase ventilation? surely "passive" ventilation would do? (it used to on all of my old UK cars...).
So surely it would be OK to just disconnect the line from the front of the rocker box to the manifold, block the hole into the manifold, block the outlet from the front of the rocker box, put a PCV valve on the rear hole in the rocker box and allow it to just vent any overpressure into the air filter? (and tidy up the rats nest of pipes around the engine and carb...)
