PCV circuit mods

[Civvy]

Could i ask the what the most popular mod is for the PCV on a N/A engine
Please keep it stricktly N/A because this topic easily gets confused with Boosted cars.

I've got two small breather filters on both PCV ofrices.
1 on the valve cover intake
1 on the black box on the rear of the block

The reason for me doing this was to stop hot oily air entering my intake. this was thought of as a good idea because of the lower intake temps and decreased chance of detonation.

I'm guessing what i have learned is correct but others are calling it questionable.

The valve cover PCV is the intake
The Black box (located on the rear of the block) is the output

The valve cover breather however, does give output at idle (with no load to the engine)

PCV is Positive Crankcase ventilation.

It is there to releive built up pressure in the crankcase caused by gasses getting past the piston rings.

The crankcase is the oil pan part of the engine and as far up as the rings are.

I've read a thread that has quite confused most on Honda-tech about applying vacuum to the black box (pcv) using a motorised pump or cleverly placing it in the exhaust pipe to create a vacuum. The purpose was to increase PCV performance.

Finnaly, the last person to comment on my set up said that it is important to have a vacuum on the black box otherwise it will have a loss over the stock PCV setup and could cause a blockage.

This person in particular has said leave the PCV system as stock.
If this was the case why do morroso sell catch cans??

I'm now guessing that i should replace by black box breather filter with an inline filter and re-connect it to the inlet manifold.

Or go back to stock.

any comments??

[lostforawhile]

Could i ask the what the most popular mod is for the PCV on a N/A engine
Please keep it stricktly N/A because this topic easily gets confused with Boosted cars.

I've got two small breather filters on both PCV ofrices.
1 on the valve cover intake
1 on the black box on the rear of the block

The reason for me doing this was to stop hot oily air entering my intake. this was thought of as a good idea because of the lower intake temps and decreased chance of detonation.

I'm guessing what i have learned is correct but others are calling it questionable.

The valve cover PCV is the intake
The Black box (located on the rear of the block) is the output

The valve cover breather however, does give output at idle (with no load to the engine)

PCV is Positive Crankcase ventilation.

It is there to releive built up pressure in the crankcase caused by gasses getting past the piston rings.

The crankcase is the oil pan part of the engine and as far up as the rings are.

I've read a thread that has quite confused most on Honda-tech about applying vacuum to the black box (pcv) using a motorised pump or cleverly placing it in the exhaust pipe to create a vacuum. The purpose was to increase PCV performance.

Finnaly, the last person to comment on my set up said that it is important to have a vacuum on the black box otherwise it will have a loss over the stock PCV setup and could cause a blockage.

This person in particular has said leave the PCV system as stock.
If this was the case why do morroso sell catch cans??

I'm now guessing that i should replace by black box breather filter with an inline filter and re-connect it to the inlet manifold.

Or go back to stock.

any comments??yes you need to leave it stock,the reason for the pcv system is to remove blowby gasses from the crankcase and burn them in the engine. on these cars clean air is pulled in through the aircleaner circulates through the block and exits at the back of the oil pan,it then goes through the liquid vapor separator (the black box on the back of the engine) the liquid oil drains back to the pan,and the vapors are pulled throuh the pcv valve and into the engine. it's important to have this system working properly through the air cleaner because under certain conditions with the pcv valve closed,vaccume is pulled from the ar cleaner box and pulled at the top of the valve cover. the system is important because it gets id of the blowby gasses and prevents them from turning into sludge into your engine. there is no performance gain from modifying it only a loss from excess crap in your motor. oh catch cans have nothing to do with performance,they are for a racing application and are designed to accumulate excess fluids. if you have a lot of pressure at your valve cover,you eithier have bad rings or possibly a plugged pcv valve. :)

[Civvy]

Why was the valve cover breather invented and commonly sold???

[lostforawhile]

well mostly for things like hot rods and such,a lot of people pulled off their pcv system thinking it took away horsepower. a functioning pcv system is not just emmisions, it really helps keep your oil much cleaner. there is a lot of misinformation on the pcv,not just on our car but on cars in general. the point is to get those blowby gasses out of the crankcase before they condense into the heavy metals,acids,water,and other crap that is left over. with a breather they just sit there, with the negative pressure in the pcv system they are pulled out and eithier reburned or they go out the exaust.

[FyreDaug]

I'm iffy about that, Gasses still get pushed out regardless if theres vacuum on one end or not, the breather filters are there incase theres negative pressure (vacuum) in the valve cover it doesnt suck in dirty air into it and get the oil all dirty. Usually its just pressure in the valve cover that you can feel in pulses. Dont believe me? Take off the filter, or the hose and put your fingers next to it, you can feel the air coming out. If you plug it, then you can get problems, if you leave a filter on it you are perfectly fine.

[lostforawhile]

oh i believe you,what you are feeling is the vaccume pulses from the pcv valve, it opens at a certain manifold vaccume,then that vacume bleeds off and it closes,it does this over and over. the reason for getting the gasses out faster is so all the crud in them doesn't precipitate out into the oil,this makes for cleaner oil. in the old days people changed the oil all the time in their cars, then engineers found that by using the pcv system it extended the life of the oil considerably. the less blowby that settles out into the oil the longer it lasts.

[A20A1]

For LX and DX models....

Why not tap into the air suction valve, that thing pulls a but load of vacuum... if it's not being used by anything else you could hook a vacuum source with check valves from both manifold and venturi vacuum to supply constant vacuum to the valve at any RPM... the exhaust gass will hopefully create the vacuum to draw out the PCV gasses.

Hopefully the valve is one-way so you wont end up turning the AS valve into another EGR valve by having it go constantly. :)

[lostforawhile]

well you don't need that much vaccume, it's already under manifold vaccume,controlled by the pcv valve. the only time you would need something like that for is drag racing,they frequently run an external vacuume pump on the case,but thats too extreme for the street.