What HE Said. Trans gears aside, the 2013-14 Vipers have 645 HP and an OE 3:55. If you have newer tires with traction, Id hate to lose 16% of your acceleration! WAIT! LOtsof owners with 650HP run 3:55s if you have good rubber.
The Year Matters too...later in you mentioned 1997. Those earlier diff carrier bolts are NOT the same size as ALL ABS and later cars. Must tap/drill for earlier cars.
Jon-
I dont want to argue... but there is a big difference between a 640 HP Gen-5 with lower bottom end torque and a final drive in the lower gears very similar to earlier cars with 3.07, and a cammed Gen-4 converted Gen-2 with huge bottom torque, 50+ HP more, and an earlier transmission with a 3.55 after it.
The Gen-5 may have 3.55's, but the only thing that matters is the final drive in each gear after the trans. The Gen-5 is
much closer in the lower gears to a earlier 3.07 car than it is to a 3.55 car. I realize you said "trans gears aside", but you absolutely cannot ignore that little detail when talking about torque multiplication through the driveline.
All that said, yes, Heath is on the cusp. He can absolutely go either way, and will ultimately be OK. Personally I lean towards less shifting and a more controllable 1/2 being less limited by tire type. At the end of the day, Gears only make your car faster between particular set points, outside of which the car gets slower. Its a trade off of feel and fun vs. shifting and control. To each their own. IMHO, the best combination going for the higher power cars is the 3.07 rear coupled with a 5/6 gear swap on a TR6060. It is a better overall spread than even the Gen-5 transmission, with lower gear loss overall.