Exceptions are few and far between that more air in from a cold air intake coupled with less restrictive exhaust will not result in an increase in HP/Torque. The added fun of cold air intake or low restriction exhaust is the sound that comes with it of course. Of the two, the greatest benefit for $$ spent will be lower restriction mufflers. There are additional benefits from other exhaust components but cost goes up quickly so the gain per dollar spent makes a sharp decline.

The best tune for a 3.0 would be one more focused on increase in TQ and a tune could easily be the clear first winner. To maximize the benefits of an airbox and low restrictive exhaust the tune would be for that particular airbox and exhaust combination. IMO a non name brand tune is not the way to go. Reliable tuners spend a lot of research to find the best map. Since the faster you want to go is directly related to how much you want to spend, how much do you want to spend?

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas