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RXWPN
30-12-2017, 04:46 AM
Hi Guys,

I have installed a larger oil catch can with 2 inputs as I wanted to make sure it was able to vent as easily as possible. I have just blocked off the factory outlet pipe and taken the larger of the rocker cover outlets instead of bridging to each other I have put one to each input of the catch can.

Is this ok or is there a better way?



79070

Confused
30-12-2017, 12:20 PM
This isn't the best place to put it. Reconnect the two heads together as they were from the factory.

Off the rear corner of the rear bank, there is the breather pipe that goes to the post-MAF inlet pipe - this is where you want to install the catch can.

Nick Mann
31-12-2017, 03:54 PM
Is there a design flow? Pcv through front cover baffles, through joining pipe, through rear cover baffles and out to intake system. So if you modify the system presumably you would need to keep a flow through both covers. It sounds like there will be no flow through the rear cover the way you have done it.

I don't know if I have made good suppositions there, but it makes sense in my head!

RXWPN
31-12-2017, 08:18 PM
I would have thought that as pressure is created in both rocker covers, it is released through the catch can which is the main point isnt it? the only thing that wont happen is that the pcv valve wont clear fuel vapours from rear bank will just pushed out through catch can instead?

Reason i did it this way was when I went to the drag racing there were a lot of turbo V8s that had massive catch cans setup this way as they said that it relieves pressure better under high boost with big turbos. But if its not suitable for our engines ill change it to factory outlet instead and rejoin the 2 covers together.

rajvr497
31-12-2017, 11:21 PM
I did the same ting you did block the line going to the front rubber piece after the and and used the front and rear ports remaining to go to my breather tank

Davezj
05-01-2018, 02:49 PM
i would have thought because you have a breather filter on the top of the catch can it will be fine to connect the catch can as you have done it.
is there a return line for the condensed vapour back to the sump of does it just catch and store the vapour.

the standard system either the engine sucks from the PCV through the baffles on the front rocker into the inlet manifold under vacuum condition only, to burn the vapour in the engine or it will get sucked/blown into the inlet pipework before the turbos from the rear rocker cover and then get sucked into the engine and burned under any engine condition. this is only if the vapour actually makes it through all the induction pipework and intercooler without condensing on one of the surfaces in there.

RXWPN
07-01-2018, 08:01 PM
Awesome thanks guys ill leave it as it is then. Its collectiing in the can so no return to sump Dave.

Davezj
09-01-2018, 06:23 PM
Most older cars you see just have vent filters on top of the rocker cover
All you really need is a bent point big enough to stop the crank case pressurising with blow by gasses.

The pcv and connection to inlet pipework are just for burning the blow by vapour. For emisions only reason.

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