Crankcase ventilation

[Peter D]

In keeping with the KISS principle, my setup is as follows :

- Edelbrock rocker covers with stock open Edelbrock breathers
- Leave one breather open
- Block off the other & fit a spigot under the sealed top
- Run a 3/16" pipe from the spigot to the main vacuum line (used for power brakes)
- Stick a 1/16" orifice restricter in the above pipe (a bit of brass rod with a 1/16" hole)

This seems to allow just enough vacuum to draw any crankcase vapours into the intake manifold (fresh air drawn in thru the open breather, fumes sucked into the manifold via the closed/spigotted breather).

With both breathers open, I could see the fumes in the rear vision mirror when stopped at the lights, and then got to clean them off the rear window & rocker covers ! With the vacuum setup described above - no fumes, no crap on the rear window or rocker covers, AND, it doesn't seem to affect the tuning at all (such a tiny bleed from the crankcase).

The pic shows the LHS blocked-off breather with the rubber tube heading off to the main vacuum line.

Kind Regards,

Peter D.