What is the part that bolts to the front of the head on the passenger side of a 2004 / 5.7 hemi engine? It has a hose that goes back to air intake. Is it necessary?
I removed mine, somebody makes a block-off kit, google it I cant remember where I found it...
I am running a aftermarket ECU (FAST XFI), so I don't know if you'll have problems with the factory ECU, i'm guessing the tuners/flash could delete it, since the kit is avail, also the 6.1 doesn't have it...
sounds like you need a flash if running a factory ECU, and the big reports are possible MPG drop 1-2 mpg's if you care, and you may burn up a cat quicker if youre gonna run one...