[Mk2] [Turbo] Catch can/breather

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rossonza
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[Mk2] [Turbo] Catch can/breather

Post by rossonza »

I'm building up a rev 3 engine. I'm looking to vent the 2 breathers on top of the rocker cover to a catch can.

Reading around loads of people have differing opinions on if this is ok.

My rocker cover has no breather valves at all. Can I just vent the holes in the cover to a catch can?

Or is it a lot more involved than that.

Thanks
Ross.
Juliuswws
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Re: [Mk2] [Turbo] Catch can/breather

Post by Juliuswws »

rossonza wrote:I'm building up a rev 3 engine. I'm looking to vent the 2 breathers on top of the rocker cover to a catch can.

Reading around loads of people have differing opinions on if this is ok.

My rocker cover has no breather valves at all. Can I just vent the holes in the cover to a catch can?

Or is it a lot more involved than that.

Thanks
Ross.


On the tuddy, one goes back to the intake manifold through a PCV valve. I guess NA is the same
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Re: [Mk2] [Turbo] Catch can/breather

Post by Race Idiot »

The NA rev3 motors dont have a catchcan, the turbo rockercover is different

Image

are you using the NA head?
rossonza
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Re: [Mk2] [Turbo] Catch can/breather

Post by rossonza »

Im using a rev 3 3sgte head and a rev 3 3sge square edged block.

will be running rev 3 turbo everything else.
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Re: [Mk2] [Turbo] Catch can/breather

Post by Ryan S »

The smaller one goes back to the inlet manifold. The larger one just vent to a catch can. The smaller one needs a PCV valve.
rossonza
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Re: [Mk2] [Turbo] Catch can/breather

Post by rossonza »

Ryan S wrote:The smaller one goes back to the inlet manifold. The larger one just vent to a catch can. The smaller one needs a PCV valve.


100% i seem to be finding conflicting ideas on both and ive seen plenty of US guys just using a catch can for the 2 breathers (AN fittings welded to rocker cover, no actual pcv valve in place).
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Ryan S
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Re: [Mk2] [Turbo] Catch can/breather

Post by Ryan S »

I don't know if it can be done but I have mine setup with the pcv valve side going to the intake. It's like that stock.
Image
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Re: [Mk2] [Turbo] Catch can/breather

Post by Race Idiot »

Man your engine bay looks so empty with all the ic/intake stuff on one side and the COP system
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Re: [Mk2] [Turbo] Catch can/breather

Post by rossonza »

Race Idiot wrote:Man your engine bay looks so empty with all the ic/intake stuff on one side and the COP system


i thought the exact same haha.
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Re: [Mk2] [Turbo] Catch can/breather

Post by Race Idiot »

Is that a Gen4 intake manifold or an aftermarket one, I do like the way you've kept the turbo>cc>intake run nice and short like that
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Re: [Mk2] [Turbo] Catch can/breather

Post by Ryan S »

It's an aftermarket/custome thing. Bought it off my mate. The wiring and fuse box has been moved to the boot too. Unfortunately we measured the wires for the coils and injectors wrong. They were supposed to be under the intake out of sight :(

Throttlebody is a Q45 just FYI :)
It'll look a lot better when I paint the rocker cover, Also...That's a genuine greddy s-type I imported from Japan. Was on my car years ago but the diaphram went. Got an uprated kevlar diaphram from NGR (or NRG I can't remember) from the states and a cheap "top hat" off a copy as the adjustment knob on the top of the original was goosed. It holds 29psi without issue so far!
rossonza
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Re: [Mk2] [Turbo] Catch can/breather

Post by rossonza »

Ryan S wrote:It's an aftermarket/custome thing. Bought it off my mate. The wiring and fuse box has been moved to the boot too. Unfortunately we measured the wires for the coils and injectors wrong. They were supposed to be under the intake out of sight :(

Throttlebody is a Q45 just FYI :)
It'll look a lot better when I paint the rocker cover, Also...That's a genuine greddy s-type I imported from Japan. Was on my car years ago but the diaphram went. Got an uprated kevlar diaphram from NGR (or NRG I can't remember) from the states and a cheap "top hat" off a copy as the adjustment knob on the top of the original was goosed. It holds 29psi without issue so far!


its like a supra intake plenum, such poshness
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Ryan S
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Re: [Mk2] [Turbo] Catch can/breather

Post by Ryan S »

It came off an evo I believe. Welded onto the correct runners obviously:) i intended to paint it but never bothered.
rossonza
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Re: [Mk2] [Turbo] Catch can/breather

Post by rossonza »

Ryan S wrote:It came off an evo I believe. Welded onto the correct runners obviously:) i intended to paint it but never bothered.


well it looks bloody lovely :-)
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Re: [Mk2] [Turbo] Catch can/breather

Post by Race Idiot »

i thought it was a 4th gen off a caldina or summat cuz those are side feed and looks pretty oem
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Ryan S
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Re: [Mk2] [Turbo] Catch can/breather

Post by Ryan S »

Yeah the caldina ones sit waaaay up at the same hight as a stock centre feed but the feed is at the side. I was actually looking for a caldina one or a modified beams one but they were insanely priced when I could find them, A very hard part to come by in the UK. My runners were cut so mine sits low down. Was all part of my master plan to keep the pipework as short as possible! It does mean there no room for an air filter (I'm looking at options) but it's been ok running with open turbo for the last 4500 miles :) Next jobs are to sort out fuel pressure, possibly alternator then have it mapped. Got 1000cc bosch top feeds for it so hoping to get close to 500bhp but having said that I'm gonna ask the mapper to dial in as much low down power as possible as it just doesn't have any torque low down(it has plenty above 4k). It's lacking what I always liked about mr2s :(
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Re: [Mk2] [Turbo] Catch can/breather

Post by Equium Duo »

Ryan S wrote:I don't know if it can be done but I have mine setup with the pcv valve side going to the intake. It's like that stock.
Image Replaced With URL For Quote https://i.imgur.com/LGPbcxr.jpg


Dude, I am now going to re-read your thread because that looks mint. Very similar to what I had imagined in my head. Love the pic of the engine.

Theres a lot fo open space in the rear right corner (where the old intercooler was). Any plans for that space or relocating anything from the bottom left corner?
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Ryan S
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Re: [Mk2] [Turbo] Catch can/breather

Post by Ryan S »

Yeah feel free to have a nosey. There was a period of time in it where i had it built up with a ct26 but i never even drove it like that! I did think about running the air filter over that side but it does mean routing piping up above the turbo. I'm not keen on that :(


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Re: [Mk2] [Turbo] Catch can/breather

Post by Race Idiot »

Having the space free over the right hand side is handy for running an oil cooler which is what I put there. But I dunno if you'd need one if you aren't tracking the car.
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Re: [Mk2] [Turbo] Catch can/breather

Post by Ryan S »

That could be a good shout actually. My turbo is oil cooled only, my oil goes black really quickly.
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