Well since your not a racer, the 3.55's should feel good, and noticeably increase performance, your looking at about 2200-23 rpm at 70mph, abouts, some factoring like wheel diameter can change it a little, I recomend subframe connectors, although that is better for a car that will be raced, although, if you want to take a turn and leave rubber like that gt, these can help you straighten out, and keep the chassis stable, tight feeling while the tires are up in smoke
your car would probaly look awesome with lower springs, wich ones i dont know? And also in my honest opinion, an x-pipe with some bassani mufflers, or flowmasters might really get you more looks than that GT that cruises around...good luck. anymore question are welcome......
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Police package 5spd 90 Lx, Stock original motor, 3.27grs, BM fan, fms 10.5 clutch, D&D quadrant, and adjuster, ADS chip, 180 stat, mac cai, mac h-pipe, mac subframe connectors, ASP crank pulley, ripper shifter, 26x10.5 M/T sport pros welds. 246 hp according to analyzer
Race weight: 3,120
E.t-13.57 with 26x10.50's e.t. streets. 1.88 60'
mph- 99.92 mph