[Kingtal0n]

Originally Posted by Croustibat

The pipes are called breather pipes for a reason; pressure goes up and down with every piston movement.

Unless you are really building pressure badly in your crankcase, you dont need to pull vacuum. You need to equalize pressure between crankcase and head, to avoid oil pooling up there and thats it.

Crankcase pressure becomes a problem when it goes so high it cant equalize, and it blocks oil from going back to the crank case. That happens when rings dont do their job anymore, which means your engine either needs a rebuild or you are pushing some tons of boost. I am talking 700+ HP territory here.

I know the current trend is all about oil mist, catch can, crank scrapers and so on. But guess what ? You dont need all that. Sure, it is "better", but the question is "do you need it". And the answer is "no". You may want it because it is trendy, it looks cool, or just any other reason, but you dont need it.



Then go dry sump. It is even better. Dont tell me you dont need it; you dont need the closed loop catch can either. and you dont need the vacuumed crankcase either.

Yes, sure, vacuum is better, as oil gets sucked down to the crankcase instead of just using gravity. But do you have oil pooling in the head ? If the answer is no, then you dont need vacuum, it is simple as that.


Yes vacuum is better, but you dont need it.

You dont need it? Then why does nearly every engine manufacturer in the world have it on their OEM engine?


Dont take my word for it, do some research.

Originally Posted by Prok0

Most people do not run a PCV setup like this, but it does yield some benefits, as you will be actively scavenging pressure out of the crank case which can promote better ring sealing and ultimately higher horsepower. If you read up on vacuum pumps or check valves in the downpipes/headers of higher hp applications pulling from the PCV you can see those guys will gain a decent amount of power by running those types of setups.