If you want the Phhhhhhhssssssssssssttttttttttt noise then get a GFB Mach1 as you also get the wastegate/turbo flutter. With the MAP sensor motor, Your ECU will NOT be able to detect the difference. AFM are the Big problem for Full Atmo BOVs. As it relies on the return of the are. Map Sensors are great, and when the ECU is cracked you'll get a nice power hike as the MAP Sensor motors are easier to Modify. My S15 had the Flutter with the GFB MAch1.