Well, my GSX has both a PCV and an EGR system. I'm referring to cars with both. I'm not sure if the B18 is equipped with it, but most cars do, domestic and import alike. I don't have a service manual for any cars equipped with a B18, otherwise I'd have looked it up before elaborating on it. Which I probably should have done.

On my GSX they're 2 totally different systems, and both of them connect to the intake manifold. On cars like the Ford Contour, Focus, and Mercury Mistake, it's actually built into the head, and the intake manifold gasket routes exhaust gas to each runner. I know for a fact that Hondas aren't set up like that, but if you have an EGR valve on whatever turbocharged race motor (whether it came with or without the turbocharger), block it off.

You certainly don't want to block of your PCV system, expecially since you've already fixed one of your blow-by problems with a catch can. That's about all you can do to that.