Review on AEM 21 488B Blue Intake System by Jose Muenzen

A significant improvement in all aspects of performance. After a week or so, check the engine light for alternating codes related to mass airflow. I strongly suspect that I stretched the mass airflow connector during installation and now I need to fix the cables (good luck finding a replacement pigtail, I'm on an ACdelco PT1504, this fix will come out in a week). Don't make my mistake, apparently common, disconnect the wire harness from the battery box before connecting it to the new input to allow for a little more freedom. I didn't remove the wheel to install mine, but I can barely get to the resonance box screws. Anyone with medium to large sized hands and arms should also consider removing the bumper. 4 stars, good product, but AEM may start instructions with a warning or two for newbies; Wire pull / access to the resonance box. I got myself a dry-flow air filter wrap just to be on the safe side, it really should be included. Update: ACDELCO Wiring Harness Part #1504 in case you stretch or break yours. Revain says it won't fit my 2008 Mazda 3 2.3L. That's right, I made it, I'm happy. Next is the Borla exhaust.