Quote:
Originally Posted by wstar
I posted a DIY when I did mine, over here: DIY - Oil Catch Can (w/ M370 + Batt Reloc). Mine's specific to my setup though (M370 intake manifold, and an empty battery compartment as a convenient location - may as well use the battery compartment heat shielding to promote vapor condensation in the can), but there's some general notes and ideas there too if you read through it.
All in all, doing your own catch can install is pretty simple once you understand where things hook up, you just have to decide where and how you'll mount/attach it.
I would think in general you'd be right about FI getting more blow-by, seems to make intuitive sense. But that just puts more blow-by into the crankcase, which is mostly fuel vapor. From there you're venting the crankcase through the PCV valve, and the crankcase shouldn't be at abnormal pressure, and most of the rest of the vapor is oil vapor from there. It may be that the rate of catch can condensation is mostly driven by crankcase pressure/airflow, which shouldn't vary much for FI vs NA. |
Actually, crankcase pressure/airflow are completely different from NA versus FI. In NA, you will never reach positive pressure inside the intake manifold. During WOT, pressure in the manifold will drop down to zero, the PCP valve will close and crankcase air will vent minimally through the crankcase vent.
However, in FI, your manifold pressure will reach up to 12 psi or whatever boost level you are running during WOT. So now the PCV valves close, but you have significantly more pressure venting from the crankcase vent to the air intake piping. How much oil vapor is blown through during this process, I am not sure.