Catch can flow discussion

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j91z28d1

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this video is blah, I don't think these engines care much about 2 sec run time till it fills the filter but also since it's a bottom mount filter that's easy to fill there's no good reason not to do it.

I did find some of his other videos very interesting, especially the 0w8 Toyota oil made by Exxon. interesting stuff.
 

j91z28d1

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select the 400$ dual one for ls engines and hit buy now lol


so I trolled myself. I was bored, watched some YouTube videos, messed around and ordered a 3 port lol.
 

BlaineBug

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Correct me if I am wrong but this is what I understand-

Passenger side PCV routing is clean air. Do not modify - leave untouched, no need to install a catch can on the passenger side PCV system (it's all connected regardless.)

IN fitting of catch can comes from driver's side valve cover PCV fitting. OUT fitting on catch can routes to the intake manifold fitting near/below the electronic throttle body.

I have a catch can coming next week, so this is what I know about it thus far.
 
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iamdub

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Correct me if I am wrong but this is what I understand-

Passenger side PCV routing is clean air. Do not modify - leave untouched, no need to install a catch can on the passenger side PCV system (it's all connected regardless.)

IN fitting of catch can comes from driver's side valve cover PCV fitting. OUT fitting on catch can routes to the intake manifold fitting near/below the electronic throttle body.

I have a catch can coming next week, so this is what I know about it thus far.


Correct-ish.

The fitting on the intake manifold that you'll connect the hose from the catch can is at the top center, not near the TB. It's where the factory hose is going. The catch can is just spliced inline in that circuit from the back of the valve cover to the top center of the manifold.

Instead of:

Out of valve cover > In to manifold

it's

Out of valve cover > In to catch can > Out of catch can > In to manifold
 

BlaineBug

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Correct-ish.

The fitting on the intake manifold that you'll connect the hose from the catch can is at the top center, not near the TB. It's where the factory hose is going. The catch can is just spliced inline in that circuit from the back of the valve cover to the top center of the manifold.

Instead of:

Out of valve cover > In to manifold

it's

Out of valve cover > In to catch can > Out of catch can > In to manifold
I'll take a look. I was watching a video from an installation, possibly from a previous generation 5.3, if there was a different PCV routing for that era.
 
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iamdub

iamdub

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I'll take a look. I was watching a video from an installation, possibly from a previous generation 5.3, if there was a different PCV routing for that era.

It's the same on a Gen 3 as it is on a Gen 4. The Gen 3 car engines (LS1, etc.) had a slightly different setup since they were more hi-po with more vacuum, higher RPM, etc. and the TB sucked from both valve covers.
 

BlaineBug

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It's the same on a Gen 3 as it is on a Gen 4. The Gen 3 car engines (LS1, etc.) had a slightly different setup since they were more hi-po with more vacuum, higher RPM, etc. and the TB sucked from both valve covers.
Isn't that how it works on the 2014/2015+ motors? There is a quick disconnect hose on both the left and right side valve covers that both lead to the monstrosity of an air intake silencer tube pre-throttle body.

One of the videos I watched showed a quick-disconnect fitting on the intake manifold beneath the electronic throttle body.
 
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iamdub

iamdub

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Isn't that how it works on the 2014/2015+ motors? There is a quick disconnect hose on both the left and right side valve covers that both lead to the monstrosity of an air intake silencer tube pre-throttle body.

One of the videos I watched showed a quick-disconnect fitting on the intake manifold beneath the electronic throttle body.

Probably. I've seen it on the 2014+ Ecotecs but never studied the routing and flow. I'm referring to the Gen3 and Gen4 engines. That's a GenV engine. I guess I'm too old school.
 

BlaineBug

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Probably. I've seen it on the 2014+ Ecotecs but never studied the routing and flow. I'm referring to the Gen3 and Gen4 engines. That's a GenV engine. I guess I'm too old school.

s-l1600[1].jpg

It looks to me as if it's sucking from both valve covers, as you can see here. With other cars and trucks I've been accustomed to in the past, normally the driver's side valve cover will connect to the air intake tube pre-throttle body and then the passenger side cover will connect to the intake manifold post-throttle body.

I suppose it doesn't matter though - I've never seen anyone on any forum talking about running a dual-catch can setup for both valve covers.
 

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