Crankcase Pressure

HandOverFist · 05-25-2016, 07:10 AM

My low buck solution and legal...

V M Kauffman · 05-26-2016, 12:29 PM

The better the engine is sealed up the less Blowby you will have which equals less Crankcase Pressure you will have. If the engine is a wet sump you can measure the Blowby with a good Blowby meter. Low leak down readings do not equal low Blowby.anything over 2cfm is too much.

Glenn Briglio · 05-27-2016, 09:14 AM

Quote:

Originally Posted by HandOverFist

My low buck solution and legal...

What does this do?

HandOverFist · 05-27-2016, 11:35 AM

Quote:

Originally Posted by Glenn Briglio

What does this do?

Just a simple path for pressure to escape.

Ron Gusack · 05-27-2016, 11:58 AM

If you have the valve cover connected to the fuel pump block off I don't think you're doing anything. They see the same pressure. I use manifold vacuum through the base of the carb and run a vacuum gauge to measure pan vacuum. It's not great but I do pull about 5 inches at the starting line. That's with both crank seals in the correct way.

HandOverFist · 05-27-2016, 12:24 PM

Quote:

Originally Posted by Ron Gusack

If you have the valve cover connected to the fuel pump block off I don't think you're doing anything. They see the same pressure. I use manifold vacuum through the base of the carb and run a vacuum gauge to measure pan vacuum. It's not great but I do pull about 5 inches at the starting line. That's with both crank seals in the correct way.

Ron - The valve cover is vented to atmosphere...the crankcase only in a torturous way. I only configured a more direct route.

Btw, the above images do not show that a breather is used on the passenger side cover. No breather/sealed on the driver side.

mike britt · 05-27-2016, 10:15 PM

Secondary air injection, and as Glenn pointed out, not legal for stock.

Bobby Fazio · 07-10-2016, 09:40 AM

I only have one breather on the passenger side of my 5.0 and no breather on the driver side valve cover. Difficult to get anything to fit on drivers side valve cover because upper plenum is in the way. I have tried open breather and have tried connecting it to the throttle body like factory. I also have the PCV valve coming out the back of the block and have tried sending that to the throttle body, sending it to the upper plenum, and just plain blocking it off. I still haven't figured out the best scenario for a stocker and I still burn some oil occasionally. Leakdown shows up fine. At the risk of sounding like a fool, are you supposed to block off PCV when you run breathers or can you run breathers along with pcv? I'm thinking that sending unmetered air back into an EFI system without the computer knowing may not be as good as a Carb system.

joespanova · 07-11-2016, 08:38 AM

Quote:

Originally Posted by HandOverFist

My low buck solution and legal...

Apparently you can't run a Dart block in stock.......because this would be pointless if you could.
The Dart block vents the crankcase through "slots" in the lifter galley like the big blocks do.

HandOverFist · 07-11-2016, 09:17 AM

Quote:

Originally Posted by joespanova

Apparently you can't run a Dart block in stock.......because this would be pointless if you could.
The Dart block vents the crankcase through "slots" in the lifter galley like the big blocks do.

Joe - That would be assuming one would want/allow the oil to drain back directly over the crankshaft.

05-25-2016, 07:10 AM	#1
HandOverFist VIP Member Join Date: Oct 2013 Location: Gulf Breeze, FL Posts: 1,651 Likes: 8 Liked 33 Times in 16 Posts	Re: Crankcase Pressure My low buck solution and legal... __________________ Rich Taylor I/SA - 321

05-26-2016, 12:29 PM	#2
V M Kauffman Member Join Date: Mar 2013 Location: Greentown, IN Posts: 113 Likes: 0 Liked 0 Times in 0 Posts	Re: Crankcase Pressure The better the engine is sealed up the less Blowby you will have which equals less Crankcase Pressure you will have. If the engine is a wet sump you can measure the Blowby with a good Blowby meter. Low leak down readings do not equal low Blowby.anything over 2cfm is too much.

05-27-2016, 11:58 AM	#5
Ron Gusack Member Join Date: Feb 2009 Posts: 244 Likes: 1 Liked 7 Times in 6 Posts	Re: Crankcase Pressure If you have the valve cover connected to the fuel pump block off I don't think you're doing anything. They see the same pressure. I use manifold vacuum through the base of the carb and run a vacuum gauge to measure pan vacuum. It's not great but I do pull about 5 inches at the starting line. That's with both crank seals in the correct way.

05-27-2016, 10:15 PM	#7
mike britt Member Join Date: Mar 2013 Location: Italy, Texas Posts: 176 Likes: 367 Liked 66 Times in 31 Posts	Re: Crankcase Pressure Secondary air injection, and as Glenn pointed out, not legal for stock.

07-10-2016, 09:40 AM	#8
Bobby Fazio VIP Member Join Date: Nov 2009 Location: Egg Harbor Township, NJ Posts: 1,468 Likes: 1,448 Liked 4,365 Times in 501 Posts	Re: Crankcase Pressure I only have one breather on the passenger side of my 5.0 and no breather on the driver side valve cover. Difficult to get anything to fit on drivers side valve cover because upper plenum is in the way. I have tried open breather and have tried connecting it to the throttle body like factory. I also have the PCV valve coming out the back of the block and have tried sending that to the throttle body, sending it to the upper plenum, and just plain blocking it off. I still haven't figured out the best scenario for a stocker and I still burn some oil occasionally. Leakdown shows up fine. At the risk of sounding like a fool, are you supposed to block off PCV when you run breathers or can you run breathers along with pcv? I'm thinking that sending unmetered air back into an EFI system without the computer knowing may not be as good as a Carb system. __________________ '65 Mustang SS/L & L/SA DriverInterviews.com \| App.DragInsights.com