Crank Case Evacuation on Daily Driver
http://www.jegs.com/i/JEGS-Performan...oductId=924093
Thanks,
Pat
One more question:
I am running a single turbo and only have single exhaust, will I be alright just running this off of one valve cover or should I do both and us a tee or something to that effect?
Thanks
It just does not seem to have enough exhaust velocity to pull a good enough vaccum on the crank case. I'm going to be taking the line off the exhaust and run it to in front of the turbo.
if you have a bunch of vac available at the air filter then your air filter is too small and costing you hp already.
just concentrate on a path of least resistance for the fumes to leave pleasantly, or add a real vacuum pump
It just does not seem to have enough exhaust velocity to pull a good enough vaccum on the crank case. I'm going to be taking the line off the exhaust and run it to in front of the turbo.
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if you have a bunch of vac available at the air filter then your air filter is too small and costing you hp already.
just concentrate on a path of least resistance for the fumes to leave pleasantly, or add a real vacuum pump
I realize this gets debated to death, but if you don't agree with filter, then where do you recommend getting vacuum on boost?
Last edited by Jwooky; Feb 25, 2016 at 09:56 AM.
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-for more hp, the only way to do that on topic is by substantial vac @16" +. that amount is not available at the intake, exhaust, or air filter when wide open. so the only option is an auxiliary pump. There is a vid online of a back to back test resulting in 20hp on 500 from atmopsheric pressure to 16" of vac.
-An air filter allowing more than 2" of vac at wide open is a measurable restriction to maximum hp. (K&N rates their filters for max CFM at 1.5"). If we insisted to run this restrictive air filter in order to gain vac to use on the crank, we would be rewarded by a proportional gain of 20*2/16 = 2.5HP
-I am not going to split hairs here but switching from oem 'restrictive' paper type air filter to K&N like we all do results in 5-15hp gain
So in summary in order to have the potential to gain 2.5hp by 'CAI DRAFT' crank vac we have to sacrifice 5-15hp on filter choice.
-an auxiliary vac pump system 'turn key' will run you $700 pretty easy by the time you get the pump, the drive, the regulator, and associated discharge catch can, then you have to keep track of turning it up and down for street driving/racing if that is the application so you do not shorten your ring/wall life.
-there are other things you can buy for $700 that may give equal or more hp
with any choice including the debated exhaust scavenging my best advice is to look closely at the math before dumping cash out. if the effect is 'hardly measurable' then the results will likely be the same.
I am not going to add a vacuum pump.
Having said that, I'm planning on the setup above. I really haven't heard an alternative.
I welcome any feedback on it.
Then a breather on the drivers side rear vacuum port of the head for the fresh air to enter the valve cover and flow across the crankcase...and exit the passengers side valve cover port.
All other ports capped off....no oil can enter the intake manifold.
Gonna install it when my turbo kit goes in. No more oil going through the top end.
.
i experimented with this setup in my research 10 or so years ago (verified by my vid quality)
The oem air pump died from oil contamination in 3 months of normal use
-oh and no tangible performance benefit.
My best advice is to find a system that controls crankcase pressure from building vs. being convinced that measured crank vac at full load is required.
if you are looking to be lied to and have someone say that there is some special way you can hook up that will make lasers and unicorns work in harmony to create substantial crank vac without hurting hp or having to buy a vacuum pump... i am not that guy.
But as soon as I capped that port off.....and started pulling from the mid port on the passengers side valve cover....the oil loss 100% stopped.
And I three new PCV valves......so it wasnt the case of a valve being stuck open.
.
the ported valley plates are baffled, some better than others
any crankcase connection to a boosted port should absolutely have some sort of blocking device, and i would not count on anything that came OEM on n/a car to do the job.
something you will have to watch out/ plan for is now that you completely close off that side of the system, there is only 1 remaining port where 100% of the fumes/blowby/oil will come blasting out of, and if your choice there is to add a second catch can (assuming you have a primary can on your pcv side) you are in effect adding more resistance to the system, and on top of the new hp driven crankcase flow you are generating, you are now restricting it through a can.
I would look for a can with very high flow on any high hp setup, if it also can block the boost, and if it can also do a good job catching the oil, and if it can allow normal pcv operation, and if it is made in the usa, upgradable and downgradable to be the last catch can you ever buy.. that would be a pretty nice solution wouldn't it!
you are right smaller/forged pistons and gapped rings can increase blowby relative to the power it makes; but the difference between power at 0 pressure and power at -16" vac remains proportional. Call it 1khp and 40hp on the table at full vac vs. 20 at 500.
Even still at the above example now you are talking 5hp gained by losing 15 with a restricted air filter (enough to make 2" of vac) (or are you losing 30 now by the same rule?)
You guys can keep wanting vacuum in the crankcase at wide open (so much that it results in hp gain) but it is just not possible without a secondary pump.
What you absolutely DO want and actually can achieve is to make sure that the fumes and blowby have as easy an exit from the engine as possible to minimize accumulating pressure, losing power, leaking a seal etc.
now for normal driving if you desire to hold zero pressure or pull a tad to the vac side that is a matter of opinion.










