Hi Alex, I have fitted the same to my engine, along with the rocker box vent I have simply piped them to a large oil catch can which incorporates a gas vent. The crankcase fitting is self made. After much thought and research I'm of the opinion the these engines can suffer high crankcase pressure as the pistons descend on the stroke especially at high rpm, much in the same way the original Mini does in high tune trim.
Ian.
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