The vanes in the intake tube add nearly 100 cfm at 1. 5" of water if I remember the #s correctly from the flow test I saw. Cummins does not add to the cost of mfg lightly.
Bob
Big rigs don't have um.
i dont work for dodge or cummins so im no expert, but i would think that the entire airfilter/intake system is built and designed by dodge. and i think that they put it there to quiet down the turbo whistle for those customers who dont like a loud vehicle.
No... It will not help performance, so leave it there.
They vanes help reduce turbulence in the air stream when the air turns the corner. If designed correctly don't have much pressure drop. Air on the inside of the turn runs into the air on the outside of the turn and causes the turbulence. Probably reduces the sound also. It keeps the air in laminar flow. If the elbow was further form the intake it would be less a problem. You don't want the turbo seeing turbulent air. Its ok for the heat exchanger side to have turbulent air, better.
The people who feel they should be left in, are saying that the cool blue hose and aftermarket intakes without the vains are losing cfm's?
I had a heck of a time to get them out of my 06 I don't think they could turn and block in my intake.
Mine was "twisted"... somehow the vanes had rotated "over-center" and the upper portion had rotated out into the airstream... if that makes any sense. I know for fact that 1/3 of the tube's cross section had became restricted...
I know it surprised me because my first thought was "glad that didn't get sucked into the turbo," followed by "I'll bet that's why my mileage is so low". Upon further inspection the vanes couldn't get into the turbo because the vanes are bigger than the turbo inlet... but it still surprised me.
I know there was a lot of discussion about leaving them in/taking them out, and while they might be a useful/beneficial addition (as shown on paper and dynos), if they cause airflow to become restricted because they move around inside the tube...
I guess since I am mostly stock and not looking for every last bit of HP (just mileage), having a laminar flow isn't as important as having an unrestricted inlet. I also don't pull the intake tube off that often like I'm sure some owners do.
steved