2) Second modification you must make is the PCV system extension. If you look at the Gen V, and locate the EVAP sensor, look to the right, and you'll see a small nipple. This is part of your PCV system, this MUST be utilized, or you WILL have a vacuum leak!! Below are your choices:
- You can run a tube from this nipple, to the air intake, this inlet must be located behind the MAF sensor, but before your throttle butterfly. In the LS1/Northstar setups, this is easily done by threading a tube into the air intake between the MAF sensor and the throttle body. On the L67 throttle body, it’s a little more involved. There is a brass plug on the bottom of the l67 tb, drill out the plug then tap it.
- You can cap this nipple off, and run a breather on the front valve cover. (***NOTE*** this allows un-metered air to enter the PCV system, and may cause problems down the road)