jwb123 - What are the bore / stroke / rod length for each combination? I'll take a s.w.a.g. the 500 was 4.380", 4.15" and 6.76"... 540 was 4.5 bore 4.25 stroke 7.1 inch rod 1.67 rod stroke ratio 500 was 4.38 bore 4.150 stroke 6.760 rod 1.63 rod stroke ratio from my memory. Like was mentioned above, the longer stroke means your average piston speed increased regardless of rod ratio. Without plotting out the complete curves for both combinations, I would only be guessing at how much min / max acceleration rates differed between them... wouldn't expect it would be that much, though.
2021 Challenger 6.4L Scat Pack 1320
100% stock: 1.680, 11.894 at 113.75 (DA 175 ft)
weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)
1973 Challenger 452 ci street/strip [2008]
pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)
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