20hp off a h-pipe install??, unit i always know your a smart guy on these questions, but i gained absolutely nothing, maybe 10hp on the topend, sound is awesome though,
i would do the subframe connectors, traction is better than horsepower when you have a near stock mustang, when you got traction, suspension tightened up, grs, then go for the hp mods, just my opinions.....good luck, could also get a monster tachometer lol.
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90 lx coupe: 5spd, energy susp trans mounts, fms hd clutch, Mac coldair fenderwell, Mac h-pipe, supercoil, ADS chip, 160 stat, aluminum D/S, Black magic fan, 3.27grs.
Best time: 13.9116(on 225/60/15 firehawks)
Best mph: 98.17
Best 60': 1.9607
someday mods:4.10's, slicks.