[MPGranger]

I once owned a Pontiac Vibe GT, aka Toyota Matrix (rebadged!). When I was younger I installed a K&N cold air intake full air system. I did see a noticeable jump in FE along with POWER, which younger me was all about. A few months later at an autozone I was bored and looked in the K&N book hanging off a chain and they were claiming a 15hp boost. I never tested the claim with anything more sophisticated than the seam of my pants. I do know smaller cars are choked by the EPA, my buddy got a intake system for his Ranger's 3L V6 and didn't see much difference.