Musclecar Showdown ~ 1968 Road Runner vs. 1964 GTO

Your comparing wrong engines...
The 64 389 4 bbl was only good for a 15.8 from MT
http://myclassicgarage.com/marketplace/knowledge_base/1964-pontiac-gto#sales-brochures

Motor Trend >
Tested the 'heavy' convertible GTO with 3.23 Gears {Open Rear}, and 3-Speed Manual.

* It 'lugged' a 15.80 @ 93.0 MPH

Road and Track >
Got their hands on a 1964 GTO 'coupe' 4-Speed with 3.23 Gears with Safe-T-Track.

They posted a respectable 15.02 @ 91.5 MPH.