MAC mufflers outflow all others (according to MAC) and are loud as hell (I've heard many sets of them, with and without off-road H-pipes)
I'm this close ' ' (haha) to buying 2.5" MAC cat-back, after months of reading, I think they'll be the best for my car now and in the future..
(mainly stock now, hopefully upto 325HP within 2 years)
BUT, if you want a quieter performance cat-back, check out Dynomax, very quiet, adds a bit of HP and torque on a stock car too..
hope that helps..
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94 GT (triple black)
FMS 9mm / 95 17" Cobra R's / AL Driveshaft / 3.27's
K&N, 12* timing, MSD Coil, 180* thermostat, 190 lph
MAC Shifter/Gauges/Pedals, Euro Clear Projectors & Corners
My CAR!