bringing up from the dead lol,
if i were to pick i'd say the 93-97 Camaros and Firebirds have a more aerodynamic nose.
and the blockier previous generation you mentioned actually had very good aerodynamics, the rear wasnt as rounded.
the concept cars you posted were prototypes for the Camaro. and actually near the end of the Fiero's life, the concepts for the next generation are extremely identical to the 4th generation Camaro/Firebird
heres one i found
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