Fitting a catch can to the car and have been having a think about what to do with the pcv valve. Ive seen some setups that have a duel catch can setup using a 2nd can in the pcv-manifold line. Is there any way I can disable or re-route the line so that my intake doesnt get mucky?

cheers

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FN2 Civic Type R w/Mugen Parts
Toyota Celica GT4 ST205
Toyota Celica GT4 ST185

I'never been sure how the PCV can function as its designed to on the 3S-GTE as this version of the 3S has a whopping big crankcase breather which routes into the intake hose via the oval black plastic catch can. If I were you I'd follow the Fensport system of routing both the PCV and the breather into a proper baffled catch can then vent to atmosphere using a small Pipercross filter.

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

I think the theory is that while cruising (most of the time on a road car) the manifold is below atmospheric pressure, thus drawing clean air in through the 'breather' and out, along with the nasty crankcase gasses, into the manifold. On boost, the PCV valve is shut and the 'breather' provides the exit route for the large (relatively) amount of blowby gasses.

Whether it is wise to remove this 'scavanging' effect, I'm not too sure. At light throttles, there isn't a great deal of blowby on a healthy engine so the quantity of oil vapour getting sucked in probably isn't huge. On a track car, it makes little odds as it's full throttle for a large proportion of the time.

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If at first you don't suck seed, try drier grain.

Yea, think I will plumb both the pcv and breather to the catchcan. The only issue I can see with this system is that it requires removal of the pcv valve

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FN2 Civic Type R w/Mugen Parts
Toyota Celica GT4 ST205
Toyota Celica GT4 ST185

Hi,

the PCV isnt't that complex, toyota built his cars also for a long periode of short distance driving where the engine never becomes hot but the oil contaminated with fuel and water
the system just has to get this out of the engine as good as possible while vacuum is in the intake manifold (gases)

i also thought about routing this line to the catch can but droped the idea in front of a to complex routing and just threated and pluged the hole

i found a nice catch can on ebay

http://www.ebay.com/itm/300535045550?it ... ae&vxp=mtr

baffeled and meshed, not bat for that price and they also did custom designs, will go with one later when i have the new engine bay situation in front of me

greetz

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KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

If I understand that correctly you have plugged the cam cover to inlet manifold breather connection which has the one way valve?
I did consider this but since I do recirculate the PCV system I decided not to as it will increase the oil fed into the intake hoses.

I was considering plugging the inlet manifold and running the pcv line to the catch can along with the crankcase breather. I will have to remove the pcv valve though.

The whole point of doing the whole exersize is to clean the intake and keep it oil free

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FN2 Civic Type R w/Mugen Parts
Toyota Celica GT4 ST205
Toyota Celica GT4 ST185

I don't see any significant advantage of running the second PCV point to the catch can rather than just blocking it unless the engine has a high blow-by that needs the extra capacity. They both come from the cam cover area and the second point would normally be closed on full chat when maximum flow is required.

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If at first you don't suck seed, try drier grain.

Hi,

keep the intake air clean of oil ist one of the best things you can do, the IC do not gets oiled and you raise the octane up to 3-4 points, so if possible do not re-route it to the engine

yes, here a picture

red plug inlet manifold, black plug on the valve cover (ST246)

viewtopic.php?f=1&t=2908&start=435

greetz

_________________
KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

when you think about it like that, I suppose it does make sense. I'll have a better look, im going to clean the car

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FN2 Civic Type R w/Mugen Parts
Toyota Celica GT4 ST205
Toyota Celica GT4 ST185

Leave the pcv valve connected to the inlet manifold as it dosen't really do anything that could affect performance. A bit of oil mist deposit on the inlet manifold runners won't hurt anything.
Route the larger cam cover breather through a catch can, then back to the intake pre-turbo. When under boost there should be a slight vacuum in the intake tract between the turbo and air filter which helps remove blowby from crankcase. This effect is obviously diminished slightly if you are running an air filter that presents less of a restriction.
A healthy engine will produce 200litres of blowby gas at high revs/load, and you want it out of the engine block asap.
PCV systems are greatly misunderstood. Running a slight crankcase vacuum can actually help the rings to seal and increase peak power.
I would not reccomend just sticking one of those tiny filters onto the main crankcase vent because 1) They will spray oil mist and mess uo your engine bay 2) they will clog quickly and present a restriction to the crankcase blowby at high load and 3) when clogged they will reduce the evacuation performance of the pcv system when cruising at light load.

If you want to go wild, remove & block up the PCV valve, and feed the large cam cover breather to the exhaust post-cat via a venturi, or to a separate electric vacuum pump.

Hi,

thats true, the PCV valve isn't a true problem as it is closed under load, you are also correct that there is a slighly vacuum in the intake hose which helps to vent the crankcase, but the oil mist
effect the detonation point heavy, not that problem on a mass produced car but on a race engine of interest to get more performance out of it, but nothing is for free you pay the bill you list with at the 3 points



i'am pretty sure that there will be not to many vacuum (or no) in the crancase when the PCV is opened, it becomes air from the crankcase ventilation back so there will
be just a flow, and then there are still cylinders that works and at least at idle i do not need power but when i need it the valve is (must be) closed


small interloop, you raise the mean effectice pressure the same points you lower the pressure in the crankcase
the exhaust point is a little bit dangerous, you must be sure at every running point of the engine that the air gets out of the crankcase and not the exhaust gas to the
crankcase
the vacuum pump isn't that perfect, nothing has a 100% efficency, the power the pump takes is more then the power you win on the engine, so why are race (!) engines out there
that use a mechanical vacuum pump then......it is a aerodynamical answer, at around 10.0000rpm the air resistance of the crank effect the power but without air (or better air/oil mix)
there is no restriction

for example, on a 3liter engine you win ~25kw at 10.000rpm, and with air in the crankcase you loose up to 30kw at 12.000rpm
but what did this mean to the 3S-GTE......correct, you will not find so much of them reving that high, 7-8000rpm drive most of us,
at this stage you loose nearly nothing even the crank has no aeridynamical design

all in all i found a simple air filter on the oil seperator is simple, cheap and the oil mist in the engine bay is not that much after some years (and protects against corrosion ), the filter itself also still works without cleaning
and is not blocked

greetz

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KEEP COOL UNDER PRESSURE

street legal?.....perhaps in tschibuti

the main reason Im wanting to do this modification is to remove oil from the inlet system entirely. This is because as I do more track time I want to reduce the risk of detonation at higher revs. I'll possibly try venting to atmosphere any see how I get on, its easy enough to revert to normal if I'm not happy

cheers guys

marcus

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FN2 Civic Type R w/Mugen Parts
Toyota Celica GT4 ST205
Toyota Celica GT4 ST185

dont know if this has been mentioned already or not but the pipe coming from the pcv to the inlet manifold runs at a negative pressure when the car is idling its only when the car is put under load or the throttle blipped that you see it reach neutral pressure

as to the breather going into the standard catch can which then has a feed going back into the rocker cover and a pipe going to the intake pipe
ive always understood that this is quite a good design coming straight from the factory and that the pipe going to the intake is to cause a pressure difference to help draw the warm air from the cam breather into the stock can
only disadvantage i see with the stock can is that it sits over a warm/hot engine and as such it doesnt help the oil to return to its liquid state quick enough hence why so many see oil in there intakes
my solution was to fit another catch can in a cooler position so as to help aid the gasius oil vapour to return to its liquid state
so far its been ok

i have no comment with the advantages or disadvantage of using the pcv area into a catch can or the breather to vent to atmosphere or both etc i just know from what ive done myself

Stock catch can is designed to act as a simple oil separator (gas enters large chamber, decreases in velocity, oil mist falls out of suspension), not condenser. Adding an additional condenser can in a cool area is a good idea if you have space available.