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Discussion Starter #1
Unless your state has strict emission regulations using a catch can is unnecessary and there are alternatives methods that work much better, offering a cleaner look with NO MESS. There are many ways to vent the PCV System but you must choose what fits your application the most. Every method has its Pros and its Cons. Please also consider maintaining your vehicle is most crucial part of your engines life. There s not a PCV System out there that’s going to help you if you don’t change your oil.

Very often threads pop up asking about the best way to achieve good crank case ventilation. It is therefore my goal here to clearly define the objectives, problems and methods involved in ending up with a good ventilation setup.

We already know that with the PCV system we are trying to achieve a few things.

1. Prevent pressure build up
2. Get water vapor and CO2 out
3. Allow clean fresh air in
4. Get oil out of the intake as oil vapors cause knock along with other problems.

Why these are good things to strive for.
1. Pressure causes leaking seals and blown dip sticks
2. Pressure causes loss of power and poor ring seal
3. Pressure causes more blow-by and more pressure
4. Water vapor and CO2 cause base alkalinity to be depleted and acids to form
5. Fresh air displaces water vapor and CO2 (oxidation of the oil is not a major concern)
6. Good vacuum causes better ring seal, more power and less blow-by
7. Good vacuum helps clear water vapor, CO2 and dissolved petrol/gasoline etc from the engine

By routing the PCV System, using the kit shown below, to the exhaust instead of the intake many things are accomplished.



1. Eliminates PCV gases return to intake thereby eliminating largest source of deposits to intake valves, fuel injectors, etc.
2. Routes crankcase gases to exhaust post-cat and post sensor
3. No need to empty a catch can
4. No chance of freezing up, unlike catch can
5. Less chance of pressure drop as could occur with a catch can

Basic PCV Setup on LSX engines are as shown.



Clean air entering the Passenger side valve cover and sucked out the valley cover. In a stock configuration it would enter the intake behind the throttle body. By attaching the valley cover to one exhaust bank and the drivers side rear port to the other bank provides plenty of suction to solve most PCV problems. Using check valves is a choice where no check valve shows greater results if you like the added level of safety they can always be used and still be effective. In fact to only method that would do better is to use an EVAC pump.

Remember your stock system will only evacuate with manifold vacuum present. This means at wide open throttle there is no evacuation at all. PCV problems become more present as horsepower and compression increases so setting this system up from the beginning is a good start.

A choice to remove your oil cap for a much nicer looking breather is also an option. As said before the system draws its air in from the passenger valve cover so if you choose to add a breather do it to that valve cover and remove the clean air feed from your air intake and plug the appropriate port .

As always if you have any questions in regard to your specific setup please feel free to contact us at Disturbed Customs.

[email protected]
 

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This is a very good write up/Tutorial

And I Thought about this a longtime ago

Running the pcv straight to my air flange located on my headers and then burning it off

But then you know I wondered ??????

Will this affect my cats and 02 sensors and subsequently
throw the tune on my car ???

Truth is I don't know

But I bet you do

How much testing have you done with the above described

Method

Thank you, Bon
 

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Discussion Starter #3
This is a very good write up/Tutorial

And I Thought about this a longtime ago

Running the pcv straight to my air flange located on my headers and then burning it off

But then you know I wondered ??????

Will this affect my cats and 02 sensors and subsequently
throw the tune on my car ???

Truth is I don't know

But I bet you do

How much testing have you done with the above described

Method

Thank you, Bon
The test vehicle that was used is a 2004 GTO with a naturally aspirated head, cam, and intake motor. It has been run and still running on this vehicle over six months now with great results. The ports would need to be positioned after your O2’s and this modification would not change any aspect in regards to the tune. For best results I would recommend an exhaust system with no cats due to velocity but before or after the cats would have to depend on the converter location. This may also may be bad for the converter as well since the deposits are not burned.
 

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I think this a fine solution for a normally aspirated track car but see some issues, especially for high boosted applications.

1) under boost there is a marked increase in crank case pressure and subsequently the volume of oil that must be evacuated. I bet, in many instances, this would look a lot like a mosquito sprayer going down the track.

2) placing the evac tubes for sufficient velocity all but ensures cat removal. big smog/inspection problem in many areas.

My solution is to either (1) install a vacuum pump system (where physical space allows) or, (2)install an oil separator between the vacuum source and the valley cover in conjunction with a fresh air source utilizing a check ball so that vacuum can be maintained and yet, when under pressure, relief of the crankcase pressure can exit - preferably through a filtered catch can.

Most supercharged applications leave zero real estate for a mechanical vacuum pump and I know of no electric vac pump that is sufficient. This leaves option 2, above, and you will need to add a check valve between the vacuum source and the valley cover.

just my $.02 worth
 

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Discussion Starter #5
I think this a fine solution for a normally aspirated track car but see some issues, especially for high boosted applications.

1) under boost there is a marked increase in crank case pressure and subsequently the volume of oil that must be evacuated. I bet, in many instances, this would look a lot like a mosquito sprayer going down the track.

2) placing the evac tubes for sufficient velocity all but ensures cat removal. big smog/inspection problem in many areas.

My solution is to either (1) install a vacuum pump system (where physical space allows) or, (2)install an oil separator between the vacuum source and the valley cover in conjunction with a fresh air source utilizing a check ball so that vacuum can be maintained and yet, when under pressure, relief of the crankcase pressure can exit - preferably through a filtered catch can.

Most supercharged applications leave zero real estate for a mechanical vacuum pump and I know of no electric vac pump that is sufficient. This leaves option 2, above, and you will need to add a check valve between the vacuum source and the valley cover.

just my $.02 worth
No there is no visual difference in the amount of smoke out the tail pipes and I have seen this used on a lot of blower cars in the past. We will have to test the set up on our supercharged camaro and release the results. Yes this set up does pose problems in smog related states but as any set up there are pros and cons.
 

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Perhaps A very small catch Can before PCV is routed to exhaust

Then a Breather on both valve covers:

Interesting topic for sure,

And sure to draw more discussion

Bon
 

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Discussion Starter #7
Here are the pictures of the newest design. The venturi tube is designed into a O2 Bung. Not only does it look nicer but also it allowed for closer clearances. The fittings are crimped to hi temp braided line. This exhaust is not stainless by the way. The original shorter test system is in storage where the older style venture tubes were used as shown in the picture in my first post. I will get a picture of that as soon as I can. This second design is what will more than likely be offered with the option to place the bung in a 90 degree or 45 degree angle.






 

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This will only work with open headers. This has been used for the past 40 plus years on drag cars. Any backpressure from mufflers, etc will blow out the one way valve and pressurize the crankcase.
 

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This will only work with open headers. This has been used for the past 40 plus years on drag cars. Any backpressure from mufflers, etc will blow out the one way valve and pressurize the crankcase.
:agree:
I would like to see an actual vacuum reading on a car with mufflers to believe this was actually providing a sufficient vacuum to the crankcase
 

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i have built a few race cars for the street and strip, and i must agree with BatCar. w/o open headers, it is not effective. been on the market for 40 + yrs. nothing new.
 

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I really don't think the OP has a clue.....went to his website and the two packages he advertises are copied & pasted right off of Hennessey's website with DC substitued for Hennessy. the EXACT articles on the test drives.....

Anyone actually had work done by or bought anything from him?
 
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