[Unreal]

Base 2015 6MT Mustang GT fastback onto the scales and it'll show 3705 lbs. That's an 87-pound increase over the 2014. With the new automatic, the Mustang GT weighs 3729 pounds, a 54-lb increase.
Going off advertised power ratings:

Ford:
Boss 302 = .122 HP per LB
13/14 GT500 = .172 HP per LB
2014 GT = .116 HP per LB
2015 GT = .117 HP per LB
*03/04 Cobra = .106 HP per LB

GM:
C7 Corvette = .138
'10+ Camaro SS = .109
'14 Camaro Z/28 = .131
'14 Camaro ZL1 = .140
*2002 SS Camaro = .095
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