Review on AEM 21 642P Polished Intake System by Douglas Coronado

I have Mazdsapseed 3 and it definitely increases performance. I notice better response when cruising around town. It also adds suction sounds followed by "piss" when you lift off the ground, which means the bypass valve is working (applies to turbos). It was very cool when I first heard it and after a few months of driving it I can say it's not annoying either. I had a hard time installing it myself, but I managed. At first I thought they gave me a filter that was too big, but it fits just fine. At least one of the best prices at the time of purchase.