Quote:
Originally Posted by DannoXYZ
Hi and welcome to Ninjette! 
Factory O2-sensor is narrowband design and only works at idle and partial-throttle to target stoich 14.7:1 AFR. Once you're into high-load operations +75%, O2-sensor is ignored and only ECU maps are used for fuel & ignition.
So PCV shouldn't be affected in any way since it's really only high-load zones that are affected by any mods you make. Factory O2-sensor is no good there and PCV can't use its data anyway. Even better is to get wideband-O2 with much more accurate feedback on AFR and PCV can use it for auto-tuning in high-load areas. Target 12.5:1 to 13.0:1 AFR for max power. Factory 300 gets an immediate +15% HP gain from leaning out factory mixtures.
As for emissions equipment, they only deal with pumping air into exhaust to clean up mixtures. It doesn't affect power in any way. So it doesn't really matter what you do. Leave it or cap it off. |
Outstanding answer! Thanks very much for the insight!