Crankcase vent
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Hmmm?
I am not sure why you'd want to and I'm sure there would be several problems to overcome. I'll watch this thread to see how it goes.
Some thoughts:
1) Where would you introduce it into the exhaust stream?
2) How would you overcome the pressure differential between the crankcase (lower) and the exhaust stream (higher)?
3) If properly designed and placed, I imagine you might be able to take advantage of the Bernoulli effect and cause a vacuum in the crankcase vent tube by using the velocity of the exhaust stream, but sizing and placement where it enters the exhaust would be critical.
4) Would the induced vacuum be reliable through the entire rpm range to supply enough vacuum to evacuate the crankcase at all times?
5) Would a stock PCV valve perform satisfactorily under a possibly different or varying amount of vacuum?
6) If placed before the catalytic converter, wouldn't the unburned oil vapor build up in it until it reached the catalyzing temperature, then be fuel for a fire, possibly ruining the cat.?
Let's see what folks say.....
Some thoughts:
1) Where would you introduce it into the exhaust stream?
2) How would you overcome the pressure differential between the crankcase (lower) and the exhaust stream (higher)?
3) If properly designed and placed, I imagine you might be able to take advantage of the Bernoulli effect and cause a vacuum in the crankcase vent tube by using the velocity of the exhaust stream, but sizing and placement where it enters the exhaust would be critical.
4) Would the induced vacuum be reliable through the entire rpm range to supply enough vacuum to evacuate the crankcase at all times?
5) Would a stock PCV valve perform satisfactorily under a possibly different or varying amount of vacuum?
6) If placed before the catalytic converter, wouldn't the unburned oil vapor build up in it until it reached the catalyzing temperature, then be fuel for a fire, possibly ruining the cat.?
Let's see what folks say.....
Last edited by MuddyAxles; Jan 22, 2007 at 08:08 PM.
FTE Leadership Emeritus
Joined: Sep 2000
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From: Stephensville WI
Race cars used to vent the crankcase into the headers, especially drag racing vehicles.
These days, they use a vacuum pump to suck out the fumes, allowing lower ring tension (less friction) but with good oil control (burning oil = lower octane = detonation = bearing failure).
These are racing engines; they live in short bursts of maximum acceleration and are not expected to last for 10 years.
Not sure why you would want something like this on your truck. The factory PCV does a great job, there would be no benefit to modifying it that I am aware of.
These days, they use a vacuum pump to suck out the fumes, allowing lower ring tension (less friction) but with good oil control (burning oil = lower octane = detonation = bearing failure).
These are racing engines; they live in short bursts of maximum acceleration and are not expected to last for 10 years.
Not sure why you would want something like this on your truck. The factory PCV does a great job, there would be no benefit to modifying it that I am aware of.
Cargo Master
Joined: Apr 2006
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From: Concord NC
diesel owners do this mod to reroute the ccv from the intake tube to the exaust or outside air. this prevents the oilly residue from pooling in the intercooler and the IC pipes.it also elliminates all the oilly mess you normaly see under the hood of a PSD.
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From: Long Island USA
Originally Posted by redford
OK, the fact he wanted to do ths to a diesel never occured to me.
Maybe something cool like a heater core used as a radiator to lower the temp of the PCV-vented fumes before routing to the intake. And a petcock on the bottom of the heater core to drain the oil every oil change.
Sorry, it's the only thing I could think of that was somewhat federal-emissions legal
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Originally Posted by 6L PWR
What's that? 
I believe that routing the crankcase emissions back into the engine was one of the first regulated emissions modifications. Previous to that the crankcase had a tube extending fron somewhere low on the block to a spot low enough to catch a passing air stream.
As a kid before I could drive I remember travelling an interstate before vehicles had that and there would be a dark greasy-looking stripe between the wheel tracks, especially on upgrades. Wouldn't that be nice to drive on early in a rain shower?
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From: Stephensville WI
Originally Posted by MuddyAxles
I believe that routing the crankcase emissions back into the engine was one of the first regulated emissions modifications.
The Feds saw the system and mandated the use of them for the 1963 model year.
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Originally Posted by MuddyAxles
I believe that routing the crankcase emissions back into the engine was one of the first regulated emissions modifications. Previous to that the crankcase had a tube extending fron somewhere low on the block to a spot low enough to catch a passing air stream.
As a kid before I could drive I remember travelling an interstate before vehicles had that and there would be a dark greasy-looking stripe between the wheel tracks, especially on upgrades. Wouldn't that be nice to drive on early in a rain shower?
Logistics Pro
Joined: Aug 2005
Posts: 3,884
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From: Morgan Hill, CA
Originally Posted by swwajk
Has anyone run a mod for the crankcase vent and tied it into the exhaust?
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