Crankcase breather, more than just emmissions?

[trublustu]

Hi all, my query is to those tech heads on the forum that understand the 1679cc SE engine better than I.
I am lucky enough to have come across a S1600 inlet which I`m grafting onto my sprint car.
This is never gonna be a bolt on like the exotic FRP inlet is.

The headaches I need to resolve are things like the ICV and servo, which isn`t too complicated.
But I cant work out how to deal with the crankcase breather.

Now I realise that this is primarily and emissions thing, but as I understand it it also decreases the air pressure inside the engine.
My physics `O` Level tells me that the pistons and oil will move easier through lower pressure air.

So what I`m wondering is...
Does the vacuum created by the inlet actually lower the pressure enough to help with engine performance. In which case I`ll have to plumb that in as well.
Or is it all just tree hugging and nothing to do with performance, In which case I can just pipe it to a catch tank with the upper breather.

I hope this makes sense, This is going to be one major project..

 

[Pkp]

I think a crankcase breather is there purely to ventilate the crankcase - when you start a cold engine, petrol will condense inside the combustion space, and may run down the bore into the crankcase. You will also get a little blow by into the crankcase.

Older cars used an open ended pipe from the rocker cover down to the underneath of the engine where the venturi effect from movement of the car would suck out the gases from the crankcase, a more modern car (like my first MkI Escort!) had a connection on the inlet manifold to provide a better "suck" !

I an aware that there have been cases of fatal crankcase explosions with marine diesels, but you won't be able to fit one of those under the bonnet of a Puma.

 

[siju]

Don't take my word for it but judging by the amount of pumas that run a catch tank I don't see this be a problem.
Also when you are WOT the inlet pressure is almost ~1 bar (absolute) so basically in this condition there is practically no difference if the crankcase exhales to the atmosphere or the inlet.

 

[drmotorsport]

Just pipe it to a catch tank which in turn breathes to atmosphere.

The original design was to meet emissions regulations and so since the 80's engines have had breath in their own manky crankcase air via the inlet valves. Its even worse now with EGR where the engine is expected to breath some of its own exhaust!