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PostPosted: February 13, 2019, 11:37 am 
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Justin,

that is what i was running with the exception of the check valve, this is how most factory systems are done except without the catch can and check valve, there are a lot of people who are having problems with oil contamination when in boost, o.k. at cruise but when in boost it isn't enough.

i am talking fresh engines here not high mileage high wear or damaged engines and it seems to be across the board, manufacturer wise

however, loads over 100% seem to be where the trouble starts, suction available at the line in the intake runner after the filter is not enough to pull the crankcase into vacuum or even maintain zero pressure, this may have something to do with line size but until i get more stuff i can't say.

it would be nice if i could get the PCV valve out from the breather plate under the intake manifold and put it where i can fiddle with it or possibly fit an adjustable one., i will remove the breather plate and look at it but its under the blower so access is not easy.

some people have added a screw to the top of the PCV valve to make it adjustable at idle, others have added a vacuum controlled breather to the top of the catch can which stays shut when vacuum is present provided by the PCV system then when it is overwhelmed by the blow by and vacuum is gone, it vents to atmosphere, alas there is no vacuum in that style system at loads over 100% to promote ring seal. but at least there are no contaminants in the inlet tract and no odd gasses in the charge, others are adding an additional PCV valve to the crankcase to handle the the idle and cruise pressure to below atmosphere.

consider this, if i were to relieve the crank case with a pipe to the outside of the MAF, the MAF would be measuring air but it would not be clean air as in 80% nitrogen and 20% oxygen, the same gasses are drawn into the intake in your diagram so the MAF signal would be reduced thus supplying less air to the engine, this would reduce the amount of fuel supplied by the PCM and the potential power at a given load would be reduced, at least that is how i see it.

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PostPosted: February 13, 2019, 8:48 pm 
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the other problem is living in the wild west, the stage coach takes a long time to get here, like i ordered stuff on sunday but it won't be here until at least next wednesday, that's eleven days of doing nothing and it may not get here then.

seriously if my neighbor sent me a letter i would not get it for 2 weeks and i would have to go to the post office to get it but they don't open till eleven o'clock and don't put the mail out in the boxes until 3 o'clock

absolutely nothing is available within 65 miles of my home and today the gas station was selling gas for $3.99 a gallon, i expect it will go up for the holiday.

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PostPosted: February 14, 2019, 2:51 am 
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john hennessy wrote:
there are a lot of people who are having problems with oil contamination when in boost, o.k. at cruise but when in boost it isn't enough.
That's the reason people recommend adding the check valve. I'd say it's worth a try...But that's just me.

john hennessy wrote:
consider this, if i were to relieve the crank case with a pipe to the outside of the MAF, the MAF would be measuring air but it would not be clean air as in 80% nitrogen and 20% oxygen, the same gasses are drawn into the intake in your diagram so the MAF signal would be reduced thus supplying less air to the engine, this would reduce the amount of fuel supplied by the PCM and the potential power at a given load would be reduced, at least that is how i see it.
On a MAF system, it gets plumbed between the MAF and forced induction system, not outside of the MAF. Otherwise you'd have an unmetered air leak under manifold vacuum. It also works in that the blow by should have minimal remaining oxygen, since it's post combustion gasses, and thus should not be metered. Does that technically reduce the volume of fresh air flow to the engine under boost? Sure. But I'm of the belief that any difference in power you felt, as a result of the amount of actual gaseous flow rate (CFM) through the PCV system relative to the total engine airflow, would be entirely placebo.

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PostPosted: February 14, 2019, 3:00 pm 
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i managed to remove the PCV valve from the breather plate on the block and have found a way to install a fitting

one question i have is do i put a scouring pad inside the breather plate?

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PostPosted: February 15, 2019, 2:34 am 
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i just couldn't resist it, went to the grocery store and bought some scouring pads and stuffed them in there.

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PostPosted: February 16, 2019, 2:45 am 
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well i've made the first part of my crankcase ventilation system,

i removed the breather plate from the block and removed the PCV valve which appeared to be working but had some carbon black deposits inside.

o fabricated a fitting with an elbow in brass to replace the PCV valve and brought the line out from under the manifod.

while the breather was off the block i installed some scouring pads in the cavity as a means of separating oil from the blow by gases before they left the breathe plate.

i mounted the baffled catch can low in the car to promote line drain to the can.

then i installed a new PCV valve to the outlet of the can in the hope that it would now be passing dry gases and piped it to the manifold after the throttle body and before the supercharger.

all the lines were done in 5/8" hose.

the intention is to give some crankcase control at idle and cruise.

i am waiting for another catch can with 3/4" ports before i install the crankcase evacuation system and vacuum switch to control the pump so as to control blow by when in boost.

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PostPosted: February 16, 2019, 8:15 am 
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KB58 wrote:
I run a dry sump on my turbo Honda K24. There's enough blowby that at idle at a light, when the wind is right it looks like I have either oil leaking onto the exhaust, or maybe an electrical short... No one's yelled at me that the car's on fire but I suppose it'll happen eventually. Somewhat related, cost aside, a dry sump is the best think you can do for an engine in a hard cornering Locost, but yeah, the cost is substantial.

I had someone argue with me that the dry sump would cost more than his engine, using that reasoning to not install it. So he goes to a trackday event, using the gas to get there, pays the $$$ entry fee, get's a hotel room, and food, and blows up his engine due to oil starvation. Okay, no problem, so he installs another identical engine. What can logically be expected to happen every time he goes to a trackday event? How many ruined events does it take to pay for the dry sump, or to completely lose interest in the car?

I'll sit down now.


There is another option that has been adopted by ferrari and bmw among others. Besides a retrofit from a bmw, one can make an accumulator system for about $200 including automatic controls. Off the shelf kits are about $500 now :ack:. I will be adding trap doors to my pan in the spit. If I upgrade to one of the newer engines that all have aluminum pans, it will get a diy accumulator.

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PostPosted: February 16, 2019, 12:11 pm 
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With judicious use of eBay or used race parts sites you can put together a dry sump system pretty cheap.

Some people look at all the bits and get brainlock, but if you can weld up a Locost, it's just a matter of studying how it works and then ordering the parts.


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PostPosted: February 16, 2019, 5:11 pm 
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Regarding accumulators, they don't provide one of the biggest benefits of a dry sump, deaerated oil.

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PostPosted: February 20, 2019, 4:35 pm 
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when i installed the larger oil pump and had to modify the pickup, i did think about a dry sump system, may be if i put a fitting in the crankcase attached to the pump and ran it down low out of the side of the block say in -10 that could then draw oil from a tank, all i would need is a single element pump to draw the oil out again, sending it to the tank and a place to locate the tank.

however as this is a road car and i don't want to loose my passenger foot well, i decided not to go that route but i still wanted the vacuum draw on the case that a dry sump would offer which i think i will have.

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PostPosted: March 1, 2019, 3:36 pm 
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so now i have a system as per Justin's diagram except that the pipe he shows to the intake just after the air cleaner is now run to my evac pump which is at the moment set with a vacuum switch to turn on at 6 Hg of inlet vacuum, this setting may change after experimentation.

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PostPosted: March 1, 2019, 3:46 pm 
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addendum to last post, i am fabricating a one way valve to fit in the line between the evac pump and the catch can to stop air being drawn in to the pump when the PCV side of the system is working like a big air leak in the crank case.

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PostPosted: March 3, 2019, 11:04 am 
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the results are in on the evac/PCV system,

at idle i have 10 inches of vacuum in the crank case, hopefully with no oil vapors, only time will tell as after some mileage i will check the catch can.

when the pump is running, there is 5 inches of vacuum and no draw through the PCV system.

this should be enough to stop any oil leaks from the seals.

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PostPosted: March 3, 2019, 9:22 pm 
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Thought of you...

I was gifted a 1962-ish MG "A" 948 motor last week. Looks like there is a big vent tube directly to the ground....

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PostPosted: March 4, 2019, 11:54 am 
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geek49203 wrote:
Thought of you...

I was gifted a 1962-ish MG "A" 948 motor last week. Looks like there is a big vent tube directly to the ground....


Ahhhh, the ol' draft tube! Common fare from the beginning, up to 1963 when the feds prohibited it.

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