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Just fitted a catch can on my gtst and getting the same thick white smoke problem on idle once engine is warmed up a little.

The reason I fitted a catch can was because I fitted a spoutles silicone turbo intake pipe with no recirculation feed from the pcv system.

I have fitted the catch can between the two cam covers as I thought it was the only way to fit with my system so not sure how to proceed?

Any advice and parts recommendations welcome.

Thanks
 

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Discussion Starter #82
White smoke on idle can be caused by several things, you will see its most of the time in these sort od temperature's and humidity, are you sure you don't have head gasket problems? the PCV system will not normally cause any white smoke, more likely burning oil if the system is blocked.
 

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White smoke on idle can be caused by several things, you will see its most of the time in these sort od temperature's and humidity, are you sure you don't have head gasket problems? the PCV system will not normally cause any white smoke, more likely burning oil if the system is blocked.
Just had a cosworth metal head gasket fitted last summer so shouldn't be that. The thick white smoke problem just started after fitting the can so not sure if I need a different setup. Maybe one of those cans with a filter on top?
 

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Discussion Starter #84
How have you got the catch can plumbed in?
 

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One pipe from each rocker cover to the two connectors on the catch can so basically the catch can is plumbed in between the two rocker covers. Like I said I no longer have a return feed to the turbo inlet as I fitted a spoutles silicone intake pipe.
 

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Discussion Starter #86
It needs to be vented either to atmosphere or ideally to the turbo intake to retain PCV.
 

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I have a bit of a suggestion question, regarding catch tank, i heard that one of the reasons why even with catch tank people still get oil in system is that the air that comes from engine is warm and moist and most of the time with cheap ebay catch cans it wont cool down enough to clean the air that goes back to turbo intake pipe...

So it might sound a bit silly but i was thinking that if you plumb in a basic few row cooler to the pipes coming from rocker covers that might cool it down enough to clean that oil and moist out of the air....

Now the setup might be a bit akward, since oil might get stuck in cooler....
What i was thinking if you mount both pipes to one end of cooler than keep that cooler sideways so the lower point will be a pipe that enters catch can but than catch can will need to be lower than oil cooler, and than you mount a pipe from catch can to turbo intake pipe just to give it that little vacuum, and if you go creative enough than you could t piece pcv one way valve in to the clean air return pipe that goes to your turbo, and to avoid on extra air being sucked from turbo intake on idle you could put another one way valve between t piece and turbo.....

Now as far as i understand this should be a perfect clean oil and moist free air going back to your turbo, and at the same time keeping the same stock idea of breather system.....

I will try to draw this setup and post a picture, because it might sound a bit confusing....

By the way im talking about RB25 engine....

Let me know what you think?

Cheers!
 

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Discussion Starter #89
A awful lot of faffing about, first off if you cool the air too much it will result in a lot of condensed water in the pipework, I have run long pipework to a fairly remote catch can and the result is a water oil mix that you certainly don't want back into the intake.

Just don't see why you would want to go to all that trouble when ether a baffled catch tank and/or SS scourers will do a splendid job of removing the oil vapor, having run catch cans on a multitude of engines I can honestly say that I have seen no real oil pooling in the intake runners or plenum on any fitted with a CT, which is the main reason for fitting, and if you remove the idle/low throttle side of the PCV system it will cut out most of the problem anyway as this is when most PCV systems shift the most suspended oil, Have a read through the entire thread and you will get more of an idea of just how it all works.
 

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A awful lot of faffing about, first off if you cool the air too much it will result in a lot of condensed water in the pipework, I have run long pipework to a fairly remote catch can and the result is a water oil mix that you certainly don't want back into the intake.

Just don't see why you would want to go to all that trouble when ether a baffled catch tank and/or SS scourers will do a splendid job of removing the oil vapor, having run catch cans on a multitude of engines I can honestly say that I have seen no real oil pooling in the intake runners or plenum on any fitted with a CT, which is the main reason for fitting, and if you remove the idle/low throttle side of the PCV system it will cut out most of the problem anyway as this is when most PCV systems shift the most suspended oil, Have a read through the entire thread and you will get more of an idea of just how it all works.

yeah i might just got a bit carried away!!! Yeah i wouldn want to have any condensation getting in the engine.... i have seen how mishimoto catch tanks look like, nothing serious inside can simply copy the setup!!!

So you recon i can get rid of pcv valve and leave it up to turbo intake pipe, that should be enough ventilation?

i heard people where talking about maintaining a minimal vacuum in engine is helpful???
 

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Discussion Starter #91 (Edited)
If you go back to the beginning of this thread, you will see a full explanation of how and why, you will maintain a vacuum if the full load side of the PCV system is plumbed back into the turbo intake.
 

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If you go back to the beginning of this thread, you will see a full expansion of how and why, you will maintain a vacuum if the full load side of the PCV system is plumbed back into the turbo intake.
O yeah i know that is just there wont be as much vacuum on idle than on pcv valve that goes to manifold.....

obviously under hard acceleration you will have some sort of vacuum between turbo and air filter since filter will give a very small resistance and create certain amount of vacuum in that pipe, besides that air flowing past air breather will cause suction out of catch tank....

And if you mount return pipe in 90 degrees inside the turbo feed pipe than it will increase even more suction.... I love Physics....
 

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Tricky,this is what i fitted the other day.Best use of scouring pads yet lol....



This pic was the first attempt.I had to do another to reposition the tails lol..
 

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Discussion Starter #95
Tricky,this is what i fitted the other day.Best use of scouring pads yet lol....



This pic was the first attempt.I had to do another to reposition the tails lol..

Nice job mate:) I see you used dividers as well, I also noticed that you moved the BOV, although the link pipe looks a little small?
So are you close to mapping time now?
 

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On the second attempt the divider was shaped to make the air go around the pads.It has hardly any restriction either.Those pads do not hinder flow.

I moved the bov the other day.Do you mean the blue link pipe Dick going from the bov?It is polyurethane air tube so looks quite thin but has the same inner diameter as the original.If it shows any issues i'll get rid ;)...Mapping today too.
 

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Discussion Starter #98
On the second attempt the divider was shaped to make the air go around the pads.It has hardly any restriction either.Those pads do not hinder flow.

I moved the bov the other day.Do you mean the blue link pipe Dick going from the bov?It is polyurethane air tube so looks quite thin but has the same inner diameter as the original.If it shows any issues i'll get rid ;)...Mapping today too.
I wouldn't worry about flow where the catch can is concerned, as long as it gets a bit of a vacuum it will be fine,

On the BOV I was talking about the pipe that connects it to the boost pipe,
Did you end up making a bend on the throttle side boost pipe, anyway I'm looking forward to hearing what it makes once mapped,
You do realise your going to have to take off all that nice stainless pipework and mirror polish it next Shaun.:D
 

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Lol,i did do the throttle side again but couldn't get a bend with a constant radius off the shelf.I made another with less extreme angles but i think i can get a silicone elbow with a swept radius instead.
 
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