LowcountryVette

I edited my post almost immediately to correct EGR pump to AIR pump, which the c5 does have and which is what goes in that hole

Kingtal0n

And I thank you for reminding me that not all engines use the port for the crankcase. I have an LS1 intake and actually blocked the fresh air port because I run boost pressure and it becomes a boost leak if left open so it was easy for me to forget its existence.

Lots of engines including supra, skyline, silvia, corolla, etc... all use a port like that to feed the crankcase fresh air. On the LS1 intake it is simply moved to just before the throttle body instead of part of the intake plastic duct work. I show a picture above from the service manual and have tested it on my own intake. As I said I blocked it because of boost pressure. Its just an open hole that leads from air filter to crankcase and my filter was replaced with intercooler cold pipe.

Good call, thanks for paying attention, we appreciate you. The port in the plastic duct may indeed be blocked as it is NOT used for PCV. However the true pcv port is merely inches away attached near throttle body and should not be ignored as it provides fresh air to crankcase in a similar fashion as if it WERE connected to that location on the duct.

Here is the blocked PCV fresh air supply in my video

1:28 you see the missing bolt is a boost leak
This is the crankcase breather for stock intake without forced induction

helga203

I untsandsand that, But all the engines i've worked on has minimal very min blow by sorry i didn't state excess blow by My car blow by a 1/2 of quart a week. My rings r gaped ..029 and .30 but it was set up that way to accommodate the high boost. I could care less what he does. If someone suggest check tire psi. That person is just trying to help. I don't care if he does or not check his tires that is not the point its a suggestion. Do what u want OP. Don't take suggestion and check. For someone to come and said that's a waste of time that's OK .. Everybody has their own opinion. I know a great place to get ur engine rebuild. If i understand what he is asking, My IQ is 56 and im proud of it. And yes im talking about N/A cars. This is what GRINDER III emailed me so this is not me. I copied and pasted this. His quote, don't hold it against him he, was over half in the bag.
He just doesn't want to be hated on here​​ by other members

Kingtal0n

The problem is you are saying that smoke is an indication of a blown engine. Which is crazy. You can't diagnose a damaged engine just by smoke from the valve cover. It needs a compression test. Whether you find smoke or not is irrelivent you still need a compression test. There is no real mechanic alive that would rebuild an engine just based on whether or not there is smoke coming out of the valve covers. It is not reliable indication of damaged engine. It is not an approved service manual procedure. It never is or will be. You take your car to the dealer and they pop the oil cap and say "yep its a blown engine- I see smoke!" find another dealer.

helga203

Im to lazy to read what i said but i thought i said it could be hurt?? But if i'm wrong. My bad. And by the way ur looking way to far into to this all i did was make a suggestion. Careless what he does.

grinder11

It's true it would need further diagnostics. However, there's only one thing that causes blowby, other than a cracked piston, and that's leaking compression past the rings. The more blowby, the more power loss...... .

Kingtal0n

I agree blow-by = lost opportunity

And, not to nitpick. But. There are a couple other things influence blow-by.
High crankcase pressure causes excessive blow-by. Its a positive feedback loop situation, more blow-by, more pressure, reduced ring function, more blow-by, more pressure, reduced ring function, etc...

Crankcase pressure forces the piston ring up earlier in the power stroke. Its called early ring switching. The ring force is balance by inertial forces and pressure forces, this situation of high crankcase pressure may leads to ring flutter which carries oil into the ring pack, causing even further reduced ring function, over time buildup causes more and more blow-by and more crankcase pressure.

If people want really clean, nice, well sealed up piston rings? Want a great piston ring seal? Measure crankcase pressure and Shoot for 0.5" to 1.5" Hg pressure drop at WOT to protect ring function.

grinder11

You have a point, also. Header evac systems and vacuum pumps create better ring seal, especially@high rpm.....

Kingtal0n

Exactly. A vacuum pump far superior suction for the ring function. Header/downpipe Evac is my favorite.

For street apps however vacuum pumps are un-wanted additional maintenance and complexity. For somebody like me who drives 10k/year non-stop I don't wana rip the front of my car apart for any reason, not even an alternator.

And if you are using a very quiet, high pressure exhaust system like OEM noise level, it is often too much pressure to evac effectively to exhaust. I've seen hit and miss success... it may become potentially unreliable in some cases.

This leaves only electric vacuum pump option and air filter pressure drop option. The electric pump has its own set of issues, the fuse may blow, it requires monitoring and a warning system for when it stops working. They also have mixed results running the pump full-time, some burn up, etc... mixed bag. Can be done but requires more setting up and potential for maintenance issues.

Which brings us to the OEM solution: air filter pressure drop. Very simple. Cannot be defeated easily, will not suddenly fail or turn off. Functions well with a restrictive exhaust system. Just needs an initial setting up, you measure, adjust, and its done for 200k miles as long as nothing really changes with the setup.
Power is related to CFM flow pressure drop at the filter so for example if I turn up the boost from 500 to 600rwhp the CFM demand increase will create additional pressure drop. Which isn't an issue- its just worth mentioning that the air filter solution entails knowledge of CFM flow rate demand at WOT to be setup correctly.