No visual here yet, but being a '96 truck with OBDII they scan it. Now I'm not sure if they just look for codes, or if they look for any other sensors that are turned off via tunning. I'd elect to have a provision for the EGR from the get go though. So that I'm able to pass the sniff and scan test. Visual will be a toss up, but I do plan on using the stock intake and air filter configuration.
A used marine intake is about $800 plus all the work that goes into one. I'm figuring there is a way to make the aftermarket intake with fuel injector provisions work with all the stock L31 sensors. Only thing that I'm not finding is EGR provision, which with the divorced EGR plate is only a drilled and tapped hole away. Now I'm not 100% sure how the EGR plumbing within the intake works, but I'm figuring it's nothing more that a passage on the front of the stock intake that dumps into the plenum. This will require some more looking into.
For the TPI intake, the stock upper portion and runners can be used (whole stock assembly with injectors and rails can be had for about $250), while buying the lower vortec intake to fit the L31 (~$400-$450). $700 or so dollars total while having all the provisions to run the motor. Only thing with this manifold will be figuring out the intake...
