Wouldn't the engine be breathing in its own vapour with that setup though? I know the primary purpose is to remove the pressure in the crankcase, but shouldn't it also remove all the moisture and blow-by gases?
Maybe I'm misunderstanding this but with the T-section isn't it venting out the crankcase stub and sucking it back in through the valve cover?
I hear what you say but with my set up there is no vacuum applied to any of the pipes, or as far as I know there isn't, its only purpose is to catch anything the engine should blow out, either through normal driving or in the event of a big bang
The engine must be breathing fairly well as if it wasn't I'd be experiencing oil leaks due to the internal pressure build and up to now the catch tank has not required any draining either, I do get a small build up of condensation on the sight pipe but that's been it
If I could find some hard facts about the HP gain from running a small vacuum pump to positivity vent the crankcase I'd make something like that work, possibly run a pipe from a stub on an air filter backplate to the rocker cover then have a 12V vacuum pump drawing on the outlet of the catch tank
