Wow -- you are the man. Actually, some people list the 327 fuelie at 375. Doesn't matter. Box stock it is still way above the Cobra 289's 306 (by your numbers).
Anyway, for a lesson in condescension just read your first post.
Thanks noob.
Anyway, the performance of the Cobra is the important component of the equation, not the rating of the horsepower. Undeniably the Cobra, in either 289 or 427 form outperformed its Chevrolet contemporaries.
Of course that's all just nostalgia, isn't it? Current Covettes have no rivals in the American car market, certainly not from the current Mustang.
(Of course you could buy 2 Mustangs and have money left over to supercharge them for what it costs to own a new Vette, but it's all about compensating with some guys.)