Just yesterday I installed an S&B CAI on my 2013 Ram. The truck is completely stock with no exhaust mods. I would say that I absolutely noticed a performance gain. It seems to be a little bit more responsive and is able to spin the tires more easily while punching it. The gain is very slight, but it is there for sure. I'm gonna have to say the S&B CAI works...
408 Stroker: 533 HP/513 FT LBS