Exhaust crankcase breather set-up - Scrapyard hunt?

[Escy]

I want to make up a crankcase evacuation set-up for my car. A couple of companies make kits but they are in America and I don't want to wait a couple of weeks for delivery for what is essentially a metal pipe and a one way valve.



I'll need a one way valve that can handle exhaust heat. The plan will be to get to the local scrappy and have a look around but just asking on here incase people have a good idea what car I could find something suitable on. Or alternatively if there is a UK seller for these that Google hasn't been able to dredge up.

[Escy]

The theory is that the exhaust flow passing that pipe creates a vacuum that will pull the crankcase gasses out (through a catch can)

[Escy]

https://www.youtube.com/watch?v=Sw1EPnEoHJM

[Escy]

There's only one way to find out.

[Escy]

Thanks for the reply. Was it one of these? https://www.worldcarparts.co.uk/valve-secondary-ve...

[Escy]

There might be some confusion, the system on the Omega is probably air injection for better emissions on cold starts rather than a crankcase breather but it'll work for what I want if I can find one so it's a good shout.

[Escy]

GreenV8S said:

I'm still skeptical that this approach will actually add significant suction to your breather catch tank (i.e. compared to the conventional dead loss vent to atmosphere) under power, and also suspect that it's going to make emissions problems even worse if you need to be road legal, but the hardware looks simple enough to make if that's something you want to try.

There are a few reasons for wanting to do it, it's going on a mid engine car where there isn't much ventilation so venting to atmosphere isn't ideal, especially if there was a leak into the cabin. Plus a small vacuum is better than none at all. I can always disconnect the pipe if it's an emissions problem.

The drawback i'm aware of is back pressure in the exhaust, people say they are no good on systems with silencers. They are typically used on drag cars with open headers in the US. I read about a tuner running one on a 800bhp Skyline on a 3.5" exhuast, it was working perfectly until they did a top speed run and the back pressure in the exhaust built up and then there is no where for the blowby to go, it shot the dipstick out and made a mess so it's something to be aware of.

I think my exhaust is perfectly suited to trying it. It's 3.5", there is a separate screamer pipe which effectively makes it bigger still and I'm going to place it after the backbox right at the end of the system. Being mid engine it's a short run to the catch can which is handy.

[Escy]

Yes, use the flow from the exhaust gas to draw a vacuum.

I don't know about flow rates but the standard breather pipe isn't that big. I expect it'll have to be quite small to draw a decent vacuum.

[Escy]

PaulKemp said:

I would think you would need a heat proof Non return in the evac pipe

Yeah, that was the reason for the thread, trying to find one suitable in the UK to save me buying one in the US

[Escy]

My search in the scrappy turned up nothing of use. I did manage to find a UK company selling one which is good although I still need a one way valve

http://www.btnperformance.com/1189-e-vac-scavenger...