NemesisC5

I'm re-plumbing my PCV system and seriously looking to pull the trigger on the KrankVent check valve PCV system. Very simple system with only two check valves that are of a patented design. I spoke with the vendor/designer and he told me the system works extremely well, so good in fact that you will not need a catch can to trap oil unless your race and your sanctioning organization requires one. The system builds a fairly high amount of CC vacuum, even to the point in some cases of makes a whistling noise pulling air through your crankcase seal (this point concerns me, but he said he is designing a variable vacuum bleed-off valve for the rew applications that may need one...just not finished yet). He also told me the system is used in many racing cars and is instrumental in ring seal where low tension rings are used. I don't plan on racing my stock bottom end but I would appreciate less oil in my intake and any efficiencies (power) gained by using this system.

The instructions on the website state that your engine must be sealed without breathers to realize the positive effects of better ring seal (more HP/TQ). Below I posted a link to a closed thread for reference. If you do a Google on KrankVent you can pull up the website, I know they are not a sponser so I didn't want to violate forum rules (I believe that's the rule). Any feedback from those who have used, or are using this system now will be appreciated

http://forums.corvetteforum.com/show....php?t=1559086

http://ls1tech.com/forums/showthread.php?t=734113

Z06PSI

I don't see how it will help with popping dipsticks. That is just a motor problem in my eyes. Vane style mechanical Evac pump is probably the best way.

longdrive70

I ran them for a while and found that they pulled a a lot of oil into the intake even with a catch can....this was due to the large amount of vacuum they allowed to be pulled. I made a vacuum relief valve which helped reduce the amout of oil ingested.

I have since them installed a mechanical vacuum pump which has worked the best so far. It was really interesting to see the amount blow by and condensation being captured.

If you are interested in a used set, let me know

NemesisC5

Never popped a dipstick....just wanting a clean intake and if I can accomplish some improved ring seal at the same time it would be icing on the cake. The KrankVents sound good but I wanted to hear real world feedback. Mech EVAC pump is the best, but I do not know any vendors offering kits for centri-supercharged applications. I thought the Mech EVAC pumps mount where your AC unit is

Where did you mount your EVAC pump?

FRCTony

It made my car squeal loudly as it sucked air thru the rear main seal. Thought I had a pulley bearing failure.

I don't see how this will do anything for oil ingestion.

The idea is good, but the squeal is a deal breaker.

AVB

You need to control how much vacuum is in the crankcase by using a relief valve like the Moroso PN# 22637

blu00rdstr

I don't get it.

Under WOT, there will be boost pressure in the intake and pressure in the crankcase from ring blowby. That pressurized oil mist has to go somewhere. If a hose carries it to your aircleaner, it's going down your intake, condensing as it hits surfaces, and getting pushed along the floor into the last runner (#7).

I call that you don't need a catch can.

AVB

krankvents don't have to be used like a PCV going back to the intake..

Warp Factor

I agree.
And besides, if the goal is to pull a vacuum in the crankcase, there won't be any vacuum at high throttle openings, which is when you'd want it most.

longdrive70

I mounted it to the front side of the passenger head. I fabricated a bracket out of billet aluminum to make sure I cleared all of the turbo charge pipes. It's powered off a tension pulley that has a 2nd COG sprocket for the pump. If you were running a centrifugal SC you could mount one on the driver side with the same type of bracket fabrication (RJW did something similar for his Whipple set up). I have about $800 invested in the who set up which has been working really well.

RED99

I had one on my harley, and it worked good for a V-twin. I'm not sure about a V-8. The way they work is you seal the motor tight (Means no breather and no PCV to the intake and no gasket leaks), when the pistons goes down, the crankcase makes pressure and the valve releases and lets it out. When the piston goes back up, the valve closes and the crankcase makes a negative pressure.
So on a V-8 where there is always pistons going down with some are going up, I am not sure how this would work.
Also, since it is vented to the atmosphere, you will need a filter on the end of the Krank Vent, and it will need to be cleaned often or it will soak up with oil and dirt.
But this is why they say you don't need a catch can. Because it's not plumbed back into the intake tract. And your cylinders will stay cleaner. But you may have a mess at the end of the Krank Vent. Oil vapers has to go somewheres.

FreddyG

Here's some old posts that talk a bit about the Krank Vent. It seems to work in principle, but sounds like it might have to be fine tuned for our setups. Good Luck Scottie!




http://forums.corvetteforum.com/show...ght=krank+vent

http://forums.corvetteforum.com/show...ght=krank+vent

http://forums.corvetteforum.com/show...ght=krank+vent

http://forums.corvetteforum.com/show...ght=krank+vent

http://forums.corvetteforum.com/show...ht=vacuum+pump

NemesisC5

Thanks Rob haven't seen much of you here lately, good to see you posting... .

FreddyG

My Pleasure and Thanks Scotty! I've been around, but just haven't posted much. Just enjoying reading and kind of hanging out seeing what's going on.

I Hope that everything is good with you!

caseyse

OEM PCVs don't seal. Nothing like heavy boost backing into your block instead of the intake. I replaced mine with a Krank Vent and couldn't be happier. I also have a hose running from my oil fill to my air filter for any blow-by. People putting PCVs there can get excessive vacuum (i.e., gaskets unseating, whistle noises).

Also have a catch can behind the Krank Vent, which works well.

NemesisC5

TLewis4095

I'm curious as to where the system draws in it's filtered make up air....and I second that any excess vacuum enough to pull ait past a seal is also pulling dust & dirt directly into the crankcase....which is never good. A Reher Morrison or Moroso vac relief valve w/a filter incorporated will cure that problem.

FreddyG

Do you have any pics of this setup or parts numbers/prices available?

Thanks!

NemesisC5

I think this might work. Cap off all ports other than ones used. LS6 valley port through check valve (to block boost) to one leg a "T" in front of CC. Driver side valve cover port (factory PCV line) into back of CC. From "T" in front of CC to Check valve then on to intake side of Supercharger or Turbo. The system will either "choose" the strongest vacuum (or maybe combined but I think the check valves will only allow one line to pull) source (intake manifold under deceleration/supercharger-turbo under boost) to pull crankcase vapors through CC. Fresh air is introduced into the system through a breather on oil filler cap. The check valves can either be the McMaster Carr units or the Krank Vent units.

It seems to me that with this system you will always have vacuum pulling fresh air into the engine that should evacuate harmful oil vapors collecting into the CC before it gets re-introduced into your engine. If anybody sees that this will not work please punch some holes in it

DRKMATTER

Scotty, your diagram looks almost identical to the way Tracy wants mine setup. Only difference that I can see is the way the CC is plumbed, but that will also depend on the type of can. On the M. Norris can I have coming, Tracy wants me to run the hose connected to the bottom of the T (hooked to your valley port in the diagram) to the bottom fitting on the CC and run the hose from the top CC fitting to the T where the valley port hose use to be....(hope I didn;t screw that up?)

We REALLY gotta straighten this out once and for all for F.I. cars. There MUST be one RIGHT way to achieve the proper goals. Sure am glad you're taking this challenge on.