PCV pipe into 75mm induction tube

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The Zork
Fast Driver
Posts: 125
Joined: Fri Jan 06, 2017 2:24 pm
Vehicle: NB SE
Location: victoria

PCV pipe into 75mm induction tube

Postby The Zork » Thu Dec 20, 2018 10:07 am

Hi guys,
I've searched high and low but cannot find fittings that will enable me to plumb into the 75mm aluminium induction pipe without welding.
Any ideas?

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hks_kansei
Speed Racer
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Joined: Tue Feb 03, 2009 10:43 am
Vehicle: NB8A
Location: Victoria

Re: PCV pipe into 75mm induction tube

Postby hks_kansei » Thu Dec 20, 2018 10:18 am

You could use something like this (obviously measure and get the size you need)

https://www.efihardware.com/products/24 ... rb-fitting

with a nut on the other side, as a crush fitting to enable you to plumb the PCV line into it.
I'd personally use some threadlock on the nut, to avoid it vibrating loose over time.
Otherwise, if you can find a castle nut that fits, use that and drill a hole for a circlip.


The other option, which I used, is to not plumb the hotside PCV into anything.
the valved PCV is the one that does the main work, with the other side acting as an inlet vent 90% of the time (except for flat throttle where it can also vent pressure)

You can use one of the little tiny breather filters on the rocker cover to filter the incoming air while allowing it to still vent pressure outwards when needed.
I personally thought it looked rubbish, so I just routed a hose from that fitting to behind my front guard, where I tucked the little filter.

Car runs exactly the same, AFRs are no different to stock (OEM ecu and O2 sensor, but I have a separate wideband and AFR gauge still installed from when I had a different ECU in the past)
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

apsilon
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Location: Sydney

Re: PCV pipe into 75mm induction tube

Postby apsilon » Thu Dec 20, 2018 10:27 am

hks_kansei wrote:You can use one of the little tiny breather filters on the rocker cover to filter the incoming air while allowing it to still vent pressure outwards when needed.


This is what I did on my old Clubman for many years without issue (though I'm not sure of the legality). IMO if you want to plumb it in then get it welded. It's a small quick job which won't cost much and you'll never have to worry about again.
'97 Neo Green limited edition


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