I have the Pro M Optimizer on my car and it works great. Last time I was on the dyno I gained 15rwhp and 14rwtq just from adjusting my AFR with the Optimizer. I'd recommend it.
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'92LX hatch, 302 w/TFS Street Heats, Performer RPM intake, Crane cam .499/.510, Crower 1.6rr, 70mmTB/EGR, Pro-M 75mm Maf, SVO 30lb injectors, BBK underdrive pullies, 190lph intank pump, BBK short headers, MAC 2.5" off road X pipe, FMS King Cobra clutch, 3.73 gears, SVO upper arms, HPM Megabite Jr. lowers, Moser forged axles, lakewood driveshaft loop, air pump removed