Lincoln Ave, I have many years building racing vehicles, including various years of Mustang Cobra (Terminators included), and also drag racing many various vehicles. You have allot to learn when it comes to understanding how rotational mass affects a street vehicle's ET in the 1/4.
I call 100% bullsh1t on your claimed 9 second Cobra. First of all if you have a 9 second Cobra you sure as hell would not be hitting those times with 19" rims and tires. Nowhere near enough sidewall to allow sufficient weight transfer to occur for achieving good launches. Thats the reason why weekend dragracers go for smaller rims with their slicks is because of that. The fella's running full tubs with large slicks care much more about getting enough traction to allow a proper launch (contact patch and sidewall) rather than eating a little horsepower to turn the tires. Street vehicles do not have anywhere near as bad of traction problems as drag vehicles do. That is the reason why it is more beneficial for them to run smaller diameter rims and also smaller diameter tires too. Being that they are only having "mild" traction issues they can get away with smaller tires with less sidewall; thus creating less rotational drag but also allowing higher potential for traction loss. Comparing drag vehicle configurations and street vehicle configurations like they are the same is usually not something that a fella who has run in the single digits does. Through the years I have been a member of many different performance vehicle forums as member, moderator, vendor, and performance business owner I have become quite adept at spotting bullsh1tters. I have observed your posting characteristics before on this forum and you fit that profile quite well.
Someone who has to qualify the content of their posts by the previous cars they may or may not have owned probably never knew much in the first place. I am not saying you know nothing, because I do believe that you aren't exactly a total newb with this stuff. Regardless of that I can still tell you have a ways to go when it comes to understanding the physics and strategy behind this stuff.
Lincoln, you can either continue being an ass in your posts 3/4 of the time or you can simmer down a bit and actually learn something from those of us who know this stuff inside and out.