Let's see some cool evac systems.

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MOPARMAGA

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My plan is to weld some -10 bungs on my valve covers and valley plate but use fittings instead of push in breathers, and make some nice baffles with something to keep the oil out of the air stream.
Anyways just wanted to see some custom stuff
 
Vacuum pump on Krusty...
Krusty engine 9-14-25.jpg


Simple pan evac system [both sides] on the Missile...
Missile hemi lft 11-22.jpg
 
I made these push-in o-ringed fittings from Delrin round stock for an evac system, makes it easy to put oil in the engine...

evac2.jpg


Separator can was made from glued together ABS pipe...

evac3.jpg


The hoses enter the can on a tangent, with vacuum pump drawing from the bottom thru a center stand-pipe. The plan was to work like a cyclone separator, any oil drops entering the can hit the outside wall and swirl around the stand pipe, more likely to drop to the bottom of the outer chamber than make their way to the center/top of the stand-pipe.

evacpcv2.jpg


Eventually eliminated the vacuum pump and just added a pcv valve to the top of the can to be used as the vacuum source.

Grant
 
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I made these push-in o-ringed fittings from Delrin round stock for an evac system, makes it easy to put oil in the engine...

View attachment 1716485275

Separator can was made from glued together ABS pipe...

View attachment 1716485277

The hoses enter the can on a tangent, with vacuum pump drawing from the bottom thru a center stand-pipe. The plan was to work like a cyclone separator, any oil drops entering the can hit the outside wall and swirl around the stand pipe, more likely to drop to the bottom of the outer chamber than make their way to the center/top of the stand-pipe.

View attachment 1716485278

Eventually eliminated the vacuum pump and just added a pcv valve to the top of the can to be used as the vacuum source.

Grant
Now that’s cool.
 
I’m going for stupid simple.
A motion raceworks can, a couple of -10 bungs welded in the valve covers and some hose.
IMG_3366.jpeg
IMG_3367.jpeg
 
I made these push-in o-ringed fittings from Delrin round stock for an evac system, makes it easy to put oil in the engine...

View attachment 1716485275

Separator can was made from glued together ABS pipe...

View attachment 1716485277

The hoses enter the can on a tangent, with vacuum pump drawing from the bottom thru a center stand-pipe. The plan was to work like a cyclone separator, any oil drops entering the can hit the outside wall and swirl around the stand pipe, more likely to drop to the bottom of the outer chamber than make their way to the center/top of the stand-pipe.

View attachment 1716485278

Eventually eliminated the vacuum pump and just added a pcv valve to the top of the can to be used as the vacuum source.

Grant
Nice job.
 
Never have seen an intake like that.. i always worried that a intake like that or a ratroaster would go off like a little bomb..
That thing is bad ***. I wish I had a video of my tunnel ram going off like a bomb from a vacuum leak. It's on of the reasons my evac system is getting redone. Thinking the backfire killed the 1 way valve.
Backfires are not allowed on my engine again.
The pushrod pinch wall is very very thin, the tunnel ram runners are very thin as well .
It will kill my junk.
 

Thanks!

After using the pcv valve proved itself as a crankcase vacuum source, I have since deleted the vacuum pump and separator can as they were no longer needed. The current evac system is a simple crossover breather setup, but I machined some internal check-ball seats for the breathers so the pcv valve could still pull a vacuum. If the crankcase ever goes positive pressure, the check valves open up allowing the breathers to serve as vents...

pcv2d.png


The pcv valve now sits between the breathers in the top of the crossover pipe. Since the above pic I have changed from the white 1" dia nylon balls to 1" dia viton rubber balls to get a better seal, turned out it was a china wall leak and not the check balls.

This setup now pulls 18"Hg down the highway without using a vacuum pump. Before crankcase vacuum, the low-tension rings would go thru a quart of oil pretty quick. After adding crankcase vacuum to the mix, maybe a quart of oil all summer...

pcv2e.png


First thoughts about this system might be, what about pulling a vacuum at wide open throttle? First, keep in mind this street/strip car typically runs WOT less than 10sec at a time. So for it a pcv based vac system doesn't need to keep up with blow-by, just needs to stay ahead of it for 10sec or less. Also keep in mind that ten seconds of 20cfm blow-by is only 1.66 cubic feet of volume, less volume than the inside of this sbc.

Data says this pcv valve on this engine only loses 1.392"Hg of crankcase vacuum per second against WOT, and the rate of vacuum loss is fairly linear. So basically if it started out with 13.92"Hg in the crankcase, it would take 10 seconds of WOT for crankcase vacuum to drop to zero. If I wanted crankcase vacuum to last longer against WOT, all I need to do is add volume to the system. Easy way to do that would be a bigger oil pan or install a puke tank, but as-is I have never seen the crankcase go positive pressure. Been using the current configuration for several years now, inside the breathers and top of the check balls are still dry.

Knowing what I know now, if I were building this system from scratch, I would just move the pcv valve and breathers to a remote puke tank. My car is begging for a gasser style Moon tank up front, might convert one into an aluminum puke tank if I run out of things to do :)

Grant
 
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I don't have an evac system since mine is a street car. I use a 'fixed orifice' pcv. (black block) It's not a traditional pcv though, there is no springcheck ball inside it, just a Holley air bleed for a constant, fixed amount of air flow. The outlet goes to the Moroso air/oil separator you see on the back of the head then back to the throttle body. I used this setup on the dyno and there was no HP loss. After I got it home, I opened it up to check for any oil and there was only water from condensation.

IMG_9390.jpeg
 
A lot of really nice setups! Lots of great thinking.
If and when I take the manifold off my hemi...it's getting a burst-panel. The car moved for the first time in 4-5 years, last weekend. Fresh battery and a splash of new fuel....it lit right up.
 
A lot of really nice setups! Lots of great thinking.
If and when I take the manifold off my hemi...it's getting a burst-panel. The car moved for the first time in 4-5 years, last weekend. Fresh battery and a splash of new fuel....it lit right up.
Nice, that thing is killer
 
I don't have an evac system since mine is a street car. I use a 'fixed orifice' pcv. (black block) It's not a traditional pcv though, there is no springcheck ball inside it, just a Holley air bleed for a constant, fixed amount of air flow. The outlet goes to the Moroso air/oil separator you see on the back of the head then back to the throttle body. I used this setup on the dyno and there was no HP loss. After I got it home, I opened it up to check for any oil and there was only water from condensation.

View attachment 1716485331
Very cool
 

I used a bolt-on -12AN bulkhead fitting that I modified to fit in the valve cover under the sheetmetal baffle that comes on the Mopar Performance valve covers (baffle is not pictured in last photo). I cut it to clear the rocker arms and the baffle, drilled a bunch of holes through it and then ran it to 2 -12 AN single fitting Motion Racework's catch cans.



Motion Raceworks.jpg


12AN Bung mod.jpg


Valve cover breather.jpg


Valve cover inside 12AN Bung.jpg
 
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