Charged K20a Prelude Type S

[RattyMcClelland]

Your PCV system wont really be working if your venting it on the valve cover. Itneeds air forced in via the intake on the valve cover side. I can see you use one of these filter on your cover.
PCV does not induce its own air. It relys on air being forced into it via the induction pipe.

I am not really sure I follow you? Air is never forced into the crank case..?

Yes it is. Not forced but vented. But it cannot suck in its own air.
For the PCV to work you need to attach a pipe from the air intake tube to the valve cover. As the engine induces air via a vacuum or a supercharger sucks in air the air passed past the PCV tube and some air is pushed into the tube and into the valve cover. This in turn vents air to remove the gasses and back into the IM or catch can then IM.

Putting a mini air filter basically stoips the PCV working efficiently so it will build up in oil and gas.

[Mudgey]

Your PCV system wont really be working if your venting it on the valve cover. Itneeds air forced in via the intake on the valve cover side. I can see you use one of these filter on your cover.
PCV does not induce its own air. It relys on air being forced into it via the induction pipe.

I am not really sure I follow you? Air is never forced into the crank case..?

Yes it is. Not forced but vented. But it cannot suck in its own air.
For the PCV to work you need to attach a pipe from the air intake tube to the valve cover. As the engine induces air via a vacuum or a supercharger sucks in air the air passed past the PCV tube and some air is pushed into the tube and into the valve cover. This in turn vents air to remove the gasses and back into the IM or catch can then IM.

Putting a mini air filter basically stoips the PCV working efficiently so it will build up in oil and gas.

Are you sure? There is no way for air to get drawn through the crankcase. the breather pipe thats attached to the intake before the throttle have a check valve to stop air from flowing into the crankcase, its one way only, and thats out. To operate effectively you don't need an air in so to speak. With my system venting directly to atmosphere I just don't end up with a slight partial vacuum at WOT.

[mercutio]

wrong buddy you need and have an in and out to create positive crankcase ventilation the pipe in the corner of the cover is the out as the intake provides suction as the air rushes past it into the throttle body the while air is drawn into the cover from the intake manifold thus keeping pressure nuetral in the engine whilst expelling gases that may leak by the valves during the compression stroke of a high comp engine.

[RattyMcClelland]

Are you sure? There is no way for air to get drawn through the crankcase. the breather pipe thats attached to the intake before the throttle have a check valve to stop air from flowing into the crankcase, its one way only, and thats out. To operate effectively you don't need an air in so to speak. With my system venting directly to atmosphere I just don't end up with a slight partial vacuum at WOT.

Wrong way round. The PCV is one way like you say.
It goes Intake>Crankcase>Intake manifold.
There is a ball bearing to stop air going from the crankcase into the induction tubing.
PCV means POSITIVE Crank ventilation.
Positive means forced heanse positive displacement pump (supercharger).
Positive pressure pushes air into the crankcase via the induction intake and this forced air through the crankcase and into the intake manifold or catch can and then intake manifold.
Putting a breather filter removes the positive pressure. No negative pressure is created to pull air in meaning gases cannot be blown by especially at WOT.
In - is via the induction tubing.
Out - is into the intake manifold or supercharger baseplate in our cases.

[Mudgey]

Are you sure? There is no way for air to get drawn through the crankcase. the breather pipe thats attached to the intake before the throttle have a check valve to stop air from flowing into the crankcase, its one way only, and thats out. To operate effectively you don't need an air in so to speak. With my system venting directly to atmosphere I just don't end up with a slight partial vacuum at WOT.

Wrong way round. The PCV is one way like you say.
It goes Intake>Crankcase>Intake manifold.
There is a ball bearing to stop air going from the crankcase into the induction tubing.
PCV means POSITIVE Crank ventilation.
Positive means forced heanse positive displacement pump (supercharger).
Positive pressure pushes air into the crankcase via the induction intake and this forced air through the crankcase and into the intake manifold or catch can and then intake manifold.
Putting a breather filter removes the positive pressure. No negative pressure is created to pull air in meaning gases cannot be blown by especially at WOT.
In - is via the induction tubing.
Out - is into the intake manifold or supercharger baseplate in our cases.

So what stops air being drawn through the crankcase and into the engine, bypassing the thorttle body? My K20 engine has one crankcase vent feeding the inlet manifold and one feeding to the intake tube before the throttle body, this latter pipe has a one way valve which prevents air being drawn into the crankcase and only allows crankcase fumes out. I had this disconnected on my engine as I had a filter there, the engine constantly hunted as it was drawing air through the crankcase filter and into the intake manifold.. ?

So the past couple days I have been busy, I have removed the head, got it skimmed, fitted ARP head studs and an OEM gasket, got the head torqued up this morning and ready for the valvetrain to be fitted tomorrow morning. Will hopefully have my LSD equiped gbox back tomorrow too and can start bolting it all back together ready to be dropped in! I've never stripped down an engine that had a timing chain before so it was quite interesting to play with something that didnt use a belt! I forgot how much honda like to use 'Honda Bond' on pretty much all mating surfaces! I think I spent as much time scraping it off as I did fitting the head back on!

Part of the strip down:


Installing the head studs:


Another view of the head studs:

[Merlin]

It is strange seeing an engine that isn't an H22 looking like that Good luck with it going back together

[NafemanNathan]

I do envy your workspace :Big Sigh:

[nucleustylzlude]

I do envy your workspace :Big Sigh:

Tell me about it. If I trip over another part, or cut my leg again on a protruding bit of gearbox I might just give up!

Great work as always Mudgey. Again, you put us all to shame. Fairplay getting stuck into your first K20 head strip down.

[Mudgey]

I do envy your workspace :Big Sigh:

Tell me about it. If I trip over another part, or cut my leg again on a protruding bit of gearbox I might just give up!

Great work as always Mudgey. Again, you put us all to shame. Fairplay getting stuck into your first K20 head strip down.

Hehe, well hopefully its comforting to know that its colder inside the workshop than out!!

Hopefully this will be my last! It was chucking out white smoke, there are no water leaks anywhere so thought its got to be the headgasket, though I haven't seen enough dodgy ones to see whether the gasket had been leaking when I took the head off. Hopefully this will cure it and as the engine was out anyway its the best time to do it. I will be doing the valve clearences tomorrow as these needed doing also..

[nucleustylzlude]

Makes sense then if the engine was out. Looks like you've got the skills to do it. Hope it cures it bud.