Crankcase Pressure. FREE HP!

05stroker

Never enough power guy!
Joined
Mar 2, 2008
Posts
13,089
Reaction score
100
Location
Bullard Tx.
just woo, glad someone else knew what i was talking about.

will it benifit a NA car. yes worth it no. too much time/money for gain/nesicity. I run an air compressor oil seperator on the drivers side and am monitoring the passenger side for necissity of another.

When i get around to my bad ass turbo build, I will be venting out the tubes.
I actually have a bung welded in my header that a catch can was attatched to but I needed a one way valve and there was not room between the trans and header for the valve and without the valve the crankcase will take on exhaust at Idle and maybe even low rpm. I now have two seperate breather cans comeing from each valve cover.
 

05stroker

Never enough power guy!
Joined
Mar 2, 2008
Posts
13,089
Reaction score
100
Location
Bullard Tx.
put the valve on the catch can
Duh! Dont know why I never thought of that . Oh well the breathers are working fine for now but if I get tired of the oil vapor I may switch it back to the can setup to the exhaust like I wanted it in the first place. Thanks.
 

Steps

Member
Joined
Nov 13, 2008
Posts
414
Reaction score
1
Location
Denver, CO
Now this is an interesting idea. Never thought of it, but could it maybe cause too much oil to be sucked out by causing a scavenger effect in the heads?


I had no issues with this setup on my F-250 PSD...a lot of the PSD guys get a bung welded into the pipe and vent everything that way, I liked it.

I have never done this on a Mustang, but I am reading carefully...
 

blackgtrag

Member
Joined
Dec 13, 2008
Posts
75
Reaction score
0
the most important part of doing an exhaust evac is the angle of the bung. the angle must be at least at 135 degrees from the flow of the exhaust. this whay it creates only a vacume and not a blow back effect. also the bung must have a small .5-1 inch tube into the exhaust to help greate the vacume. if you have any issues just adjust the angle of the bung.

as for stroker, dont worry the obvious is usually the hardest to see when your the one doing the work,

as for pacettr yes your will gain power but mostly TQ as it frees up the valvetrain to work more efficiently... think an underdrive pully its reducing drag and parasitic loss within the motor
 

05stroker

Never enough power guy!
Joined
Mar 2, 2008
Posts
13,089
Reaction score
100
Location
Bullard Tx.
the most important part of doing an exhaust evac is the angle of the bung. the angle must be at least at 135 degrees from the flow of the exhaust. this whay it creates only a vacume and not a blow back effect. also the bung must have a small .5-1 inch tube into the exhaust to help greate the vacume. if you have any issues just adjust the angle of the bung.

as for stroker, dont worry the obvious is usually the hardest to see when your the one doing the work,

as for pacettr yes your will gain power but mostly TQ as it frees up the valvetrain to work more efficiently... think an underdrive pully its reducing drag and parasitic loss within the motor
Ok well as soon as I am back up and tunned I will ck out the exhaust evac with the Stefs can in line and out to both sides of the engine (as this is how I started out for it to be). I would like to test the crankcase psi on this vs the breather setup I have under boost . If less crankcase psi = hp then haveing the exhaust sucking on the Stefs can would be better than breathers and not have the vapor at the redlights, but first thing first the car must be back on the road . LOL!
 
Joined
Dec 4, 2008
Posts
411
Reaction score
3
Location
Jax FL
I may be mis understand this thread but why cant you just put a breather where the oil cap goes or will to much oil get in it?
 

CataclysmGT

Member
Joined
Jul 20, 2008
Posts
191
Reaction score
0
I don't get the entire thing. Being Whippled, the PCV outlet goes to the compressor suction. Under full load, the supercharger is going to be sucking hard, and reducing crankcase pressure a lot. I have a catch can between the PCV outlet and the supercharger, and it collects a fair amount of oil. Its obviously working.....
 

Eric298

Got V8?
Joined
Nov 1, 2008
Posts
212
Reaction score
0
Location
Virginia
I don't get the entire thing. Being Whippled, the PCV outlet goes to the compressor suction. Under full load, the supercharger is going to be sucking hard, and reducing crankcase pressure a lot. I have a catch can between the PCV outlet and the supercharger, and it collects a fair amount of oil. Its obviously working.....

+1 thats what I was thinking.

but I think Dex runs a turbo so he doesnt get this feature the way you have it because of the boost before the tbody vs yours being after. Thus the power increase hes getting by removing the cap? :idea:
 

eng943

Member
Joined
Apr 29, 2008
Posts
461
Reaction score
0
I'm confused...

So are we saying that just using breathers in place of the PCV on the top of the valve covers is not a good idea?
 

don_w

Dyno Numbers - Who Cares?
Joined
Apr 4, 2007
Posts
9,999
Reaction score
103
Location
San Diego, CA
I'm confused...

So are we saying that just using breathers in place of the PCV on the top of the valve covers is not a good idea?
There are many people who run breathers only... myself included.
 

ZmanM3

The Evil One
Joined
Apr 6, 2007
Posts
21,617
Reaction score
210
Location
Jackson, NJ
I may be mis understand this thread but why cant you just put a breather where the oil cap goes or will to much oil get in it?

Yes breathers would work fine. A remote breather with a catch can will just reduce waste oil from dirtying up the engine compartment.

I don't get the entire thing. Being Whippled, the PCV outlet goes to the compressor suction. Under full load, the supercharger is going to be sucking hard, and reducing crankcase pressure a lot. I have a catch can between the PCV outlet and the supercharger, and it collects a fair amount of oil. Its obviously working.....

I am sure that I get this same benefit but the problem is the blow by oil that makes its way into the throttle body. This can cause problems with a sluggish idle or surging because it messes up the reading that the throttle position sensor gets.

+1 thats what I was thinking.

but I think Dex runs a turbo so he doesnt get this feature the way you have it because of the boost before the tbody vs yours being after. Thus the power increase hes getting by removing the cap? :idea:

Yes he is relieving pressure in his crank case.

I'm confused...

So are we saying that just using breathers in place of the PCV on the top of the valve covers is not a good idea?

We are saying it is a good idea. Breathers good for reducing crank pressure. They just dirty the engine bay.
 

Eric298

Got V8?
Joined
Nov 1, 2008
Posts
212
Reaction score
0
Location
Virginia
Yes he is relieving pressure in his crank case.

quote]

Thanks anywayz I already knew the reason of the increase and power and the facts discussed in this thread.

I was trying to ask it almost as a question towards him as to start a conversation over the way he has his set up vs the way dex has his setup with the turbo as im under the impression that he is using a twin screw where as the suction of the supercharger causes a vacum to relieve pressure where as dex cant get his setup this way because the pressure is before his throttle body leading to my statement slash question of "thus the increase in power? :idea:" Just saying^^^
 

kenneth

Senior Member
Joined
Aug 6, 2007
Posts
1,795
Reaction score
7
Location
Louisiana
after reading this whole thread my mind is more warped than before.
I see DEX had positive results with a turbo setup.
How would this work with a twinscrew setup?
 

Dex

I'm Dexolishous
Joined
Apr 3, 2008
Posts
3,808
Reaction score
13
Location
Utah
I had a lot of blow by. I had my motor taken apart and rebuilt by Adam so I'll have the breather on and the regular cap on to test it.

Make run. cool down 5 minutes, run with cap. cool down 5 minutes, run with breather.
 

kleistang

Senior Member
Joined
Oct 14, 2007
Posts
2,408
Reaction score
6
Location
Miami Florida
old thread but i have a couple of questions. i was running a catch can on the driver side, and yesterday i decided to make a T and add the passenger hose that was going to my intake tube, to the catch can. ok so when i did this and i started the car it started running fine but i started hearing a moam sound from the front butom end. and i was like WTF ! so i took the oil cap off it was tight and there was a lot of suction there. with the cap off i put my hand in the hole and right away started to feel the suction and the moam sound came back. so i umpluged the passgener side and left the hose hanging still conected to the T and put the oil cap back on. the moam went away.

basicly what i saw was, the passenger side sucks air inside (i would think this is why it was conected to the intake tube, which i dont really think is a good idea when im running nitrous) and the driver sides takes air out (and oil comes with it) into the intake manifold.

so i figure i would leave the catch can on the driver side like it was before and do a breather on the driver side.

please comfirm if this is right, or there is something wrong with my motor lol
 

Latest posts

Support us!

Support Us - Become A Supporting Member Today!

Click Here For Details

Back
Top