modern day muscle cars are far from inefficient. you only have a select breed of cars you can brag about. mainly the skyline and the supra. both pushing $60k + price tags new. a 96 tt supra still goes for $30k in decent shape. if you want tp compare those cars be prepared to go against vipers, vettes, saleens, ligenfelters, exotics etc...
an 03 cobra comes stock with 390fwhp hp. they actually dyno 360-370 rwhp which puts that 390 to more like 430fwhp. do you know how much ground your cute little 4 cylinder has to make up to even consider catching up? that car is also only $34k brand new. your top end wrx and lancer is approx. $28-30K.
dont compare a 1,000 hp v6, cause i can come back at you with a 5,000+ hp drag car

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when it comes to best bang for the buck, and most easily modified the v8 is always gonna be on top. imorts can be made fast, but wrx's sure like to break those awd trannys. the last 3 times ive been at the track theres been at least one that broke cause of tranny failure.
i drag race all the time, and get sick of the whole ricer "fast and the furious scene". its way out of hand with too many misinformed ricers.
me personally i dont like old muscle cars, i like new modern muscle.
and dont come back with the good ol' hp per liter saying if a mustang was as efficient as a ricer car it would be 500+hp stock.
cause if all cars were as efficient as a yamaha r1 that makes 150hp per liter then the s2000 would be 300hp.
lets not forget about torque either? imports have none, which is why they need turbos, and awd vehicles. you ricers have no idea what your missing till you drive something with "TORQUE"