Factory "catch-can"?

[Mr. Wyndham]

You can tell it's really not a catch can, not like the after-market ones....but I was pleased to see this attempt at preventing atomized oil from being sucked right into the LSA....

I only had a short moment to poke around the engine bay today...tomorrow or Tuesday I hope to get a closer look...maybe it can be emptied? What's inside? etc...

[radz28]

Is there anything in the manual about servicing it? Maybe that's a one-way check valvd of something if not. I gad a catch can and TWO oil seperatoes on my '02 and it used a lot of oil for being a bolt-on car with a converter. I had no detonation problems after sdding them though. This is going to be an area I'll be looking into, too.

Thanks for the pics'!!!

[Mr. Wyndham]

Originally Posted by radz28

Is there anything in the manual about servicing it? Maybe that's a one-way check valvd of something if not. I gad a catch can and TWO oil seperatoes on my '02 and it used a lot of oil for being a bolt-on car with a converter. I had no detonation problems after sdding them though. This is going to be an area I'll be looking into, too.

Thanks for the pics'!!!

At first, I thought all it was was a check-valve....but then I noticed that it extends past where it connects to the intake tube by about 4 inches (can't see this very well in the pictures).

[99firehawk]

I have a Magnuson TVS 2300 on my Magnum and that looks like the supplied oil separator that came with the Maggie kit. It used the same tee dual-PCV hose feeds into a smallish black round collector.

I already had a larger catch can and used that. If indeed this is the same or similar unit, you don't need to empty it as the bottom of the collector had a hose that fed somewhere (can't recall but will get my install doc and look).

[radz28]

Originally Posted by 99firehawk

I have a Magnuson TVS 2300 on my Magnum and that looks like the supplied oil separator that came with the Maggie kit. It used the same tee dual-PCV hose feeds into a smallish black round collector.

I already had a larger catch can and used that. If indeed this is the same or similar unit, you don't need to empty it as the bottom of the collector had a hose that fed somewhere (can't recall but will get my install doc and look).

If it goes back into the intake somewhere, that's just a waste, lol. I can't see it doing anything else because of hydrocarbons. I'm very interested to see though

[Russell James]

If it's going to the valve covers, wouldn't that be the clean air in side of the PCV?

An actual catch can would need to be connected between the valley and intake. This piece looks like it just deals with the fresh air going in the valve covers.

[Mr. Wyndham]

Originally Posted by Russell James

If it's going to the valve covers, wouldn't that be the clean air in side of the PCV?

An actual catch can would need to be connected between the valley and intake. This piece looks like it just deals with the fresh air going in the valve covers.

There is a line going from the valley cover to a vacuum port aft of the throttle-body.

I checked it out closer today - it's definitely not a "catch-can" as we know them...you can't open it, and there's no drain...but at the same time - I don't think this is just a supply of fresh air. I could be wrong....

[radz28]

I agree that it couod be a check valve or regulaor for crankcase pressure while under boost. Since it's pulled back into the throttlebody, it's probably not a true catch can unfortunately. That's what the aftermarket is for

[SC2150]

It is a checkvalve to work with the boost. It does help slightly and this is a good move....but it needs to be taken alot further.


The little unit that comes with some of the maggies now is a home air compressor separator and lets a ton of oil past, but the worst part is they have it set up to return the trapped oil full of damaging contaminates back to the crankcase......very bad over time. The oil caught in any oil separating device is so contaminated with the harmfull combustion byproducts you absolutely NEVER want them returned back to the crankcase.

[radz28]

Originally Posted by SC2150

It is a checkvalve to work with the boost. It does help slightly and this is a good move....but it needs to be taken alot further.


The little unit that comes with some of the maggies now is a home air compressor separator and lets a ton of oil past, but the worst part is they have it set up to return the trapped oil full of damaging contaminates back to the crankcase......very bad over time. The oil caught in any oil separating device is so contaminated with the harmfull combustion byproducts you absolutely NEVER want them returned back to the crankcase.

It definately sounds like a separator or catch can (or both) is the way to go to keep the system clean and motor healthy.

[Russell James]

Originally Posted by Dragoneye

There is a line going from the valley cover to a vacuum port aft of the throttle-body.

I checked it out closer today - it's definitely not a "catch-can" as we know them...you can't open it, and there's no drain...but at the same time - I don't think this is just a supply of fresh air. I could be wrong....

Yes, that's the fresh air supply for the crankcase. Air comes in the valve covers (filtered air from the intake tube) to replace the crankcase vapors going out the valley to the intake vaccum port.

That device must have something to do with the different conditions the PCV sees under boost.

You could put a catch can in there in the traditional spot of between the valley outlet and intake vaccum port.

[SC2150]

Russel is correct on all aspects of how this system works.

The downside to this configuration is if you begin to mod the car then the valey cover fixed orfice becomes too restrictive to vent properly, but it is a MUCH better set-up than the LS3. With the air entering both valve covers and flushing to the valley cover the entire crankcase/valvetrain gets flushed and the damaging compounds removed. The Cadillac CTSV uses the same configuration. This is GM's best solution to date IMHO.

A catchcan is STILL critical on this or you will see the intercooler looking like the pictures I have posted and you surely dont want any detonation with FI.

[Mr. Wyndham]

Originally Posted by Russell James

Yes, that's the fresh air supply for the crankcase. Air comes in the valve covers (filtered air from the intake tube) to replace the crankcase vapors going out the valley to the intake vaccum port.

That device must have something to do with the different conditions the PCV sees under boost.

You could put a catch can in there in the traditional spot of between the valley outlet and intake vaccum port.

Gotcha. Thanks for the clarification. It could be a small expansion "tank" for changes in pressure...maybe.

Originally Posted by SC2150

Russel is correct on all aspects of how this system works.

The downside to this configuration is if you begin to mod the car then the valey cover fixed orfice becomes too restrictive to vent properly, but it is a MUCH better set-up than the LS3. With the air entering both valve covers and flushing to the valley cover the entire crankcase/valvetrain gets flushed and the damaging compounds removed. The Cadillac CTSV uses the same configuration. This is GM's best solution to date IMHO.

A catchcan is STILL critical on this or you will see the intercooler looking like the pictures I have posted and you surely dont want any detonation with FI.

No, I definitely want to install a catch-can....I'm waiting to recover a bit more from the initial purchase before I start buying mods, though....I like to have a very fluffy "cushion".

Do you guys have a ZL1-specific mounting place, yet?

[SC2150]

It appears the Long "L" will work fine, but post up pics of the engine bay showing the passenger side area.