Whenever you replace or mod a part that has to do with the amount of air flow being changed you need a tune.
Unless its something small like a CAI, but even then would best to tune it, this will need it more then most other Mods.
When I bought a 2.3L motor I had a OEM header that was cracked when I looked up to see what the cost of a new one was I about Shat myself was More then HALF the price for a OBX header.. but I promise you that cops will turn heads more, my 2 speeding tickets over last weekend will attest to that.
One ticket was for a cop who said she PACED me at 90... However I never went over 70, she was under the bridge at the on ramp I got on, she heard me gas up fast and that turned her head my way, if this was my other OEM car, I would never had gotten her attention.