There are two tricks to driving both Vipers and Cobras very fast...
#1 A good full face helmet
#2 Earplugs
You'll hardly notice the speed... Not that a big-block at 4800 rpms steady is something that can totally be drowned out.
As to top speed, I heard that the open Cobras turned 190+ at LeMans...and that was with a puny 500 hp or so, and I know MANY of you have that much HP at least. I'm sure someone can do a quick top speed calc based on their 1/4 mile times, HP, gearing...
The general thought is that the Cobra body has bad aerodynamics above 145... Porsches, Vipers, etc. are pretty much rock solid though, I've been in a few up near 170. We have a guy around here with a twin turbo Viper that says he routinely hits 200 mph on public roads...Maybe youve seen it, its got the American Flag/Eagle flames, been in a few mag articles.
Heres a link
http://www.supervipersystems.com/Upg...stage_iii.html