OK guys here is a simulation that assumes both cars are driven correctly, no cross eyed drivers, no stupid driving mistakes just two cars correctly operated and measured through a qtr mile. I'll let you look at the specs in the individual pics but they are publicly availably from various sources mfgr/internet etc.
Bottom Line is more HP/Lb always wins. The Cobra has 0.213HP/# while the Viper is only 0.171HP/#. The Cobra has 25% more HP for each # of car it has to accelerate and it is lighter! The outcome of the match up is pre-ordained. The Viper is no match for the Cobra! The only way the Viper can win is if the Cobra driver is a wus or doesn't know what he is doing.
Absolute power is not as important as HP/#. In fact it can be a detriment when the vehicle is heavier. Light cars can run just as big a tire as heavy cars. The difference is they are lighter, launch harder and do not have as many traction problems as heavier cars.
Here are the simulations:
First the Cobra
Then the Viper
The Cobra spanks the Viper by almost a second through the quarter and 4MPH despite a worse coefficient of drag and a larger frontal area! By the way a one second difference in ET is like watching two different races that's how bad it is.
If you really have 550 HP in your Cobra, know how to drive it and have the stuff to drive it, there are precious few cars that can keep up with you. Even fewer can outperform you!
Ed
<Begin Edit>p.s. This fictitious Cobra is probably very similar to Greg's Schroeder's car in the post just before mine.
<End Edit>