PCV oil breather
PCV oil breather
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dm240

Original Poster:

6 posts

66 months

Tuesday 31st March 2020
quotequote all
Hi, i am looking for advice for routing the engine blow-by.
There is all sorts of advice out there regarding PCV delete etc, I wondered if anyone could give me first hand results please?
I have an LS376/525 motor, I’ve flipped the inlet 180 degree, I’ve cobbled everything together first just to start the engine to check for leaks and it works fine.
Just to get it started I have hosed the Valley cover dirty air to the original point just after the throttle body, hosed the clean air to the inlet in between the MAF and throttle body and have put a breather on the rocker cover dirty air.
Ideally I want to run an air/oil separator / catch tank, any tried and tested advice please.
Thanks Rob

Boosted LS1

21,200 posts

276 months

Tuesday 31st March 2020
quotequote all
There is already an oil/air separator underneath the valley plate, So imo keep it original, clean air into the valve covers from after the MAF so it counts as metered air. Dirty air from the valley plate into the plenum. That's what I'd try.

xrtim

260 posts

123 months

Tuesday 31st March 2020
quotequote all
I’ve done a similar thing regarding the installation of the engine and getting it running, my breather system vents from the engine rocker cover into an oil separator that I have made for the engine and gearbox, the oil drains to a catch tank down by the offside rear wheel with a site tube and quick drain tap for emptying. The clean air form the separator splits and then goes back to each turbocharger intake. Engine runs fine no miles on it so all theory for the long term ( don’t get much blow by from engine as running total seal ring package).
Regards Tim

Boosted LS1

21,200 posts

276 months

Tuesday 31st March 2020
quotequote all
^ Have you got air flow into the engine crankcase ie a pcv circuit Tim or is it just the vent's from the rocker covers to the tank?

xrtim

260 posts

123 months

Tuesday 31st March 2020
quotequote all
I have also got a dry sump pump pulling oil and air out of the engine to a tank and this also venting to the oil separator along with the rocker cover and gearbox.
Tim

dm240

Original Poster:

6 posts

66 months

Tuesday 31st March 2020
quotequote all
Thanks for the info guys, I'll try stock to start with I wasn't aware of the air oil separator under the valley cover. If I get any oil build up I'll have a look at running a similar set up to yours Tim.
Thanks Rob

xrtim

260 posts

123 months

Thursday 2nd April 2020
quotequote all
Picture of what I made showing it’s construction , may be of some help. Stainless steel wire wool placed inside and lid screwed on.