I'm not just quoting factory specs, I talk/work with some that were around when those cars were developed (at least the GM ones).
The only way any Factory-Stock GTO (Judge, RAIV even) would beat a LS6 450hp 454 Chevelle is if the Chevelle driver gives the GTO a 1/2 sec advantage off the starting line in a drag. NOBODY focused is that bad.
All things even, the 1970 Chevelle SS 454 LS6 beats ALL the other similar GM cars (Lemans/GTO, Skylark/GS, Cutlass/442).

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !