Funny you should mention this. I noticed that my oil pressure varied throughout the RPM range, and got noticeably higher when downshifting. I wondered if crankcase pressure might be causing this. Eventually I found that the hole in the intake manifold (the one that the small tube from the valve cover connects to) was undersized due to epoxy around the fitting. Since I drilled that out the oil pressure remains constant throughout the RPM range.Hey folks-
I ported the the outlet hole by .25 inches when I initially started working the engine over. I then routed the outlet hoses to a vented oil catch can which is mounted just forward of the right side engine mount. The return venting hose is the same diameter and mated on the forward portion of my cold air intake, just aft of the filter.
I have found that my oil pressure has finally stabilized through all RPMs and (!) there has been zero oil return through the intake.
just thought this might help in the whole decision bit. Have a great one!