One of my 455’s has the PCV valve on the passenger side. The other engine has the PCV valve is on the driver’s side.

I’m not sure which is right.

The one on the passenger side has cleaner oil for longer & runs smoother. The one with the PCV on the driver’s side, runs a bit rougher (could be the cam...) and the oil gets dirtier quicker.

What’s the conventional wisdom on which side the PCV should pull through?

Looking forward to your thoughts & opinions.

Chris

 

I don't think it really matters. Either way should have the same effect, the only difference is the air flows in opposite directions through the system.

 

It depends on the year of the car, but it doesn't really matter, Olds moved them back & forth over the years. My '68 442 has it on the pass side, the next few years it was on the drivers side. My girlfriends '76 Salon/350 has it back on the pass side. The main thing is that it's hooked up or you'll get oil leaks.

 

And some performance versions even had them attached at the front of the intake...

 

1968 motors had the PCV valve in the passenger side valve cover. 1969 moved it to the driver side. 70 W30 and 455 MT cars had it at the front of the intake. As noted, from a functionality standpoint it doesn't matter - the PCV just needs to be in a location that has access to the crankcase volume. The air cleaner really dictates the location, since the factory air cleaners have the vent opening (that goes in the opposite valve cover) in a specific location each year.

 

69 H/O had it in the intake as well. All of those intake PCVs used the dual breathers on the valve covers IIRC.

 

Gents,
Many thanks for your quick replies. I just found it weird that my 2 66’s had one on each side.

I suspect one or the other was switched during some engine rebuild or installation at some point.

Glad to hear it doesn’t matter and that the air cleaner and other clearances can dictate.

cheers
cf