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I am considering adding an oil separator between the PCV valve and the vacuum port on the carb/manifold.  I am interested in seeing how much oil is being pull into the manifold.  I recently re-ringed the engine and thus it may not be much but it may good to know.  Are any of you running this setup?

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...Yes, I run two. One at each Rocker Cover. I invented them. They allow ONLY Vapor to Pass, Does Not Collect Oil, But Allows it to Drain Back into the Cover. They are, Also, Transparent, and will not allow a 'Burp' or Crankcase Surge to Pass Oil, into the Carb. They allow for Maximum Engine Breathing in Both Directions. NO oil is 'Missing' off the Dipstick, Period!


Last edited by marlinjack

...Why do You think You need a 'Catch' Tank??? So You can 'Save' Black Smelly Oil, and Look at it, as You drain the Tank Out!!

I figured these 'Vapor Seperators' Out, with these parameters, with attention paid to the Physics of Gases and Liquids...Vacuum and Gravity.

As said long ago...I hated Breathers!! They stink! and The, what little, Fumes/Smoke, comes up and over the decklid and is seen in the rearview mirror.


1) NO Catch tank, absolutely INCLOSED System.

2) ONLY Vapor is Burned in the Engine, NO Oil is to Enter the Manifold, and Especially Not to enter the Carburetor.

The Design:

1) The PCV Valve is inserted into the Right Rear Rocker Cover. Oil is Stopped at the First 90 Degree fitting, this acts as a Restrictor, The Seperator, itself, acts as a 'Expansion Chamber' where Vapor 'Can' Form. From there, the Vapor is drawn into the Manifold at a fitting Below the Carb. On the Manifold NOT the Carb.

2) The Second Seperator is at the Forward Left Cover. From the Exit, the Vapor is delivered Under and up through the Filter Plate, and exits Inside the Filter, Between the Filter and Opposite the Holley Primaries. NO Oil has ever Appeared Here! No Hose clamps are needed here, as we are dealing with Vacuum, and the Hoses Fit Tight.

The Physics:

The Two Systems MUST NOT be In-Line...The 90 Degree Fittings are the KEY! This is a Restriction, that Dis-allows 'Suction' of the Oil, Along with the Expansion Chambers.

The Entrance to the Seperator MUST Be lower than the Exit! This allows for a 'Drain Back' into the Covers, by gravity and by the reversed direction of the Air Flow, as in Idle...WOT...idle.

Being transparent the Expansion Chambers provide Proof , No Oil is getting to the Manifold and Carburetor! As Witnessed when removing the intake Filter...On the Carb, No Oil, No Dirt!

That about covers it. Any Questions, Ask.

P.S. Anyone Still want a Catch Tank?? I have one for Sale, NEW. I'll post a Picture....Gorgeous Chrome Steel, about a Quart or Less. Photos to Follow!

Last edited by marlinjack

...I will Post this on Parts for Sale. Just putting it Here so YOU will see it First!

'Engine Oil Blow-By Catch Tank'. With Drain Valve and Swivel Fittings.

NEW Beautiful Chrome Finish. Never Used Never Installed. A few Very Light Scratches from Storage, being moved around in the shop, Always in  a Cardboard Box!

3" Diameter...8" Tall, fittings Not in Measurement. I Believe the Capacity is near a Full Quart.

Chrome Fittings, as They Came with the Tank! 90 Degree Swivels to Alignment.

Chrome Drain Valve, as came with this Tank, Fine Smooth Action.

Way to 'Pretty' for My Pantera! Belongs in Your 'Show' Pantera! And I do Not want a 'Catch Tank'!

Will Stand Out in Your Pantera Engine Bay! A one of a kind, hard to find, Beauty.

This Tank Is NOT polished Aluminum, IT IS Thickly Show Chromed STEEL. It is Heavy and very nicely made.

Yours for $125.00 Shipping in USA is FREE!!

I just listed it on Ebay for the Same Price. This Tank can also be used as a 'Vacuum Tank', 'Coolant Over-Flow' Tank, 'Oil Storage' Tank, Etc.

Be the First...or have this Sold Out from Under You!!

Last edited by marlinjack

I am using one also although a bit more conventional then Marlin's.

You can see the catch tank on the left. It has two lines, both stainless hard lines. One comes from a vent on the left valve cover and the other goes to a vacuum manifold that is hidden in this picture under the header heat shield.

The tank has an external clear/tinted tube that will show you the contents of the tank and there is a petcock drain on the bottom.

In all honesty it doesn't catch much oil per se but does accumulate mostly water.

The system isn't as much of a catch tank as it is an oil scrapper.

My Audi TT turbo has a very similar set up although much more low key and winds up with just about the same level of water and sludge. It really never gets to the level of needing to be emptied. So you really can't prove the necessity of needing a scraper system like this BY ME...BUT YOU ASKED!


Images (2)
  • Pantera Fuel Injection 1
  • Pantera Fuel Injection 4
Last edited by panteradoug

There are actually 3 bungs. The one you mentioned at 90° is actually being used now for the fuel injection sensor. It isolates the sensor the most from failure from water in the exhaust.

I don't like where I have to put the o2 sensors but there is not a lot of flexibility with them generally speaking. They just take up way too much room for their actually size.

They are essentially the same exact part that was introduced 40 years ago or so and nothing has been done to improve the flexibility of application. It's as though the manufacturers are making us all do penance and will blame it on "the Government"?

I personally think that there is plenty of room both in original manufacturers application and aftermarket to re-engineer these things and for the manufacturers to show that as a group they can have some original individual thinking and not be just another group of sterile numb nuts, however the current offerings would tend to indicate otherwise?

Last edited by panteradoug

I just wanted to add that the initial reason that I installed this system with a "catch can" is that you will find that if you want to run a closed high speed event at a race track, you will be required to have a "oil catch can from the valve covers" installed and functional.

That is what they want to see. If it gets too fancy it likely will be self defeating and rejected.

The tech people REQUIRE the can otherwise you will not be permitted on the track with the car.

A drain back is irrelevant. They are just minimizing the risk of oil spilling on the track.

I would think, the simpler, the better.

Last edited by panteradoug

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