I'll chime in as a former Cobra owner, and the owner of two blown S197's.
Cobra > S197 GT in almost every way, except for comfort and features.
I do not see a properly driven Cobra losing to a 360ish RWHP GT.
I raced dozens of different types of Blown 3V's when I had my Cobra (Still had my GT at the time I had my Cobra too) My Cobra would pull steady on all of them. Granted, it was not "rape" by any means, but a Cobra's 3rd gear is very long and pulls very hard.
It takes a blown GT with supporting mods to realistically beat a Pullied Cobra with an experienced driver.
Give you an example of an inexperienced driver. When my Cobra was stock, with just suspension (Road raced car) I ran a KB Cobra putting down over 600 RWHP, and it weighed 100lbs less with the driver. Long story short, after 4 consecutive runs, each time was no more than 3/4 of a car. Cobra's are not easy cars to drive, they are very rough, yet forgiving if you miss gears and grind.
I love my S197 GT's, and would never go back to a Cobra since they are now outdated, and the 5.0 is the way to go, but, I will still acknowledge that performance wise, they beat the S197 dollar for dollar, and mod for mod.