LT1-LT4 Modifications 1993-97 Gen II Small Block V8

PCV Exit As Vacuum Source?

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Old Feb 29, 2016 | 03:20 PM
  #41  
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Originally Posted by Shownomercy
So if there is blowby, and its an OEM motor, its bad?
Why would anybody desire blow by? The idea is to minimize it in the build, and then deal with it for as long as you need to run the engine. You can run an engine with poor sealing character and massive blow-by. High performance small displacement engines (2.6L) with large ring end gaps might pass a jug of oil on a 7 second pass, but we just catch it and dump it back in and make another pass until the head blows the hood off the car.

OEM engines should not produce significant blow-by, so in general, YES if there is BAD blow-by coming out of an OEM engine, then something is wrong, most likely rings or ring related since that is really the only place for combustion gasses to escape (examine the picture I posted above, the brown arrows floating around show where combustion gasses are coming from, and going to). There can also be a situation where the "check valve(s)" go bad, and this can simulate blow-by since it pressurizes the crankcase when the check valve goes bad. That is why adding additional check valves is never a good idea, more points of failure.
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Old Feb 29, 2016 | 03:22 PM
  #42  
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Interesting, you should prob send a letter to GM to let them know!
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Old Feb 29, 2016 | 03:26 PM
  #43  
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Originally Posted by Shownomercy
Interesting, you should prob send a letter to GM to let them know!
Oh believe me, they know, I've been exposed to the out of round bore engine situation, GM wont do anything about it apparently.

http://www.corvetteforum.com/forums/...post1590266523
Originally Posted by FYREANT
:iagree: Good info! One of the big challenges we C7 owners face through all of this is when excessive oil ingestion is experienced, (resulting in an eyebrow raising moment when emptying a catch can) GM does not want to start tearing engines apart to fix the issue. Proof of this can be basically seen as when you complain of this at the dealer they require you to take an "oil consumption test" where you log the oil level on the dipstick over the course of 5000 miles or so. Thats all and great but the issue I have with that is they clearly put on the document that consumption (burning OR ingestion) of a 1 quart of oil per 500 miles when the vehicle is used for hard acceleration is "NORMAL". I'm sure we can all agree to disagree with them on that. Its downright stomach turning that they consider that much oil loss "NORMAL" :ack:

Ant

http://www.corvetteforum.com/forums/...post1590538587

@hrcslam
Originally Posted by Joe@CPR
So you have it pulling in air post maf sensor? Why not throw a check valve there too like a mighty mouse can so it only opens under boost and is sealed when under vacuum. This way no un-metered air gets in.
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Old Mar 5, 2016 | 11:47 PM
  #44  
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Originally Posted by Snorkelface
I spoke to Mr. Mouse and have everything figured out. I'm going to use my breather on the passenger valve cover for now that's routed to the suck side of the turbo intake, but I'll probably get a hollowed out PCV valve and stick a breather on that later.

I just didn't realize that the PCV exit location could be used for the fresh air inlet based on my assumption of how everything flowed, but I understand it will sere the purpose well. Now time to get it tuned soon!

BTW, I found an awesome location to mount the can. I'll try to get some pics before she goes.
Hey, did you get a chance to mount the can? What spot did you use?
I'm liking MM's reasonings, they seem to match what I'm looking for out of a cc. Looking to buy from him soon.
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Old Mar 6, 2016 | 12:34 AM
  #45  
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I mounted mine below the driver's side hood shock tower or whatever it's called towards the front of the engine bay. It fits perfectly and there's a hole in the bottom making draining easy. I'll try to take a closer pic tomorrow.

Originally Posted by Evaporate
Hey, did you get a chance to mount the can? What spot did you use?
I'm liking MM's reasonings, they seem to match what I'm looking for out of a cc. Looking to buy from him soon.
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Old Mar 6, 2016 | 04:33 PM
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Cool thanks. And glad to see yours is back on the road. It's been a good long wait with hiccups for me too.
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Old Mar 6, 2016 | 07:00 PM
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Once I get this misfire nailed down and find a smog guy she will be. Haha

Here are a few pictures of my catch can install. I hope it helps! She's tucked nice and tight in there. No need for a mounting bracket. I put a little double sided tape on the bottom just to help it from scratching from the car.

Originally Posted by Evaporate
Cool thanks. And glad to see yours is back on the road. It's been a good long wait with hiccups for me too.
Attached Thumbnails PCV Exit As Vacuum Source?-20160306_165109.jpg   PCV Exit As Vacuum Source?-20160306_165145.jpg   PCV Exit As Vacuum Source?-20160306_165304.jpg  
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Old Mar 6, 2016 | 07:28 PM
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Ok. And what size lines and fittings did you go with? Sending you a pm about another question as well.
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Old Mar 6, 2016 | 08:18 PM
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Here's some pics of my MM can that I just installed. He also made a custom bracket so I could mount the can to the drivers side head where my coil used to be.
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Old Mar 6, 2016 | 09:09 PM
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I'm running a -10AN to the can, then a 3/8" hose back to the intake.

Originally Posted by Evaporate
Ok. And what size lines and fittings did you go with? Sending you a pm about another question as well.
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Old Mar 6, 2016 | 09:53 PM
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Thanks again snorkelface. Looks like we have the same bov, seems loud for my taste (loud and wide open at idle). Your cc location might be just where I'll put mine due to lack of space with all the blower crap everywhere.

Huntr that's a clean bay. Like the mounting bracket too.

You guys tap your valve covers yourselves? Is there a preference for which vc to tap? Could've sworn the ps one was the preferred, if not both???
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Old Mar 7, 2016 | 12:19 AM
  #52  
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Just buy a weld-on bung from a parts store, then take it and your valve cover to a local welder. Shouldn't be more than $40-$75 for them to weld it on. Poking the hole through is the easy part. Haha

Not sure if there's a preference there since the stock valve cover already has a tap on top, that might be why it's more common. I would ask Mr. Mouse, but he didn't mention any preference when I told him I was going off the driver's side vc.

Originally Posted by Evaporate
Thanks again snorkelface. Looks like we have the same bov, seems loud for my taste (loud and wide open at idle). Your cc location might be just where I'll put mine due to lack of space with all the blower crap everywhere.

Huntr that's a clean bay. Like the mounting bracket too.

You guys tap your valve covers yourselves? Is there a preference for which vc to tap? Could've sworn the ps one was the preferred, if not both???
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Old Mar 7, 2016 | 07:30 AM
  #53  
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I would put the bungs at the front of the engine so at WOT you don't blow out oil.
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Old Mar 10, 2016 | 04:04 PM
  #54  
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Sorry, I thought I had replied here with the pics. Here's my catch can mounting. fits and works great, plus it will be relatively easy to drain, even after adding the bottom panel back on.

*EDIT* I'm not sure why this site rotated the last picture, but the can is mounted upright.
Attached Thumbnails PCV Exit As Vacuum Source?-20160306_165109.jpg   PCV Exit As Vacuum Source?-20160306_165145.jpg   PCV Exit As Vacuum Source?-20160306_165304.jpg  
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