My car's top speed

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Well, a little fun and games with math. I believe 65Shelby's estimates are close. It's my opinion that a stock 5.0 could reach 140, but only a really good one, and one with steeper rear gearing (like 3.73's) to allow the engine to access the peak power band in high gear. I think a more reasonable estimate for a stocker is 130-135 mph. Let's assume that's done with 190 rwhp. Increasing top speed on a car is a function of HP (assuming you don't change aerodynamics) and the additional HP required is a cubic function related to the speed increase. For example, Let's say it takes 190 rwhp to hit 135 mph. To approximate what it would take to hit 200 in the same car (you have to assume it's regeared so peak hp occurs at top speed) the math says - 200/135 = 1.481. The amount of power needed to hit 200 mph is 190HP X (1.481 cubed).
That's 1.481x1.481x1.481x190 = 618 rwhp to hit 200mph in the same car.

So, if you know how much rwhp you have, and you have an idea of the power curve - at what rpm that peak power occurs, and you do some calculating with your tire size and gear ratios so you know what speeds occur at what rpms, using the relationship above, you can play some guessing games on top speed potential. But it's impacted by so many variables that actual testing is ultimately the only way to really know.

But, if you want to play games, here's a formula based on the math set forth above. All HP's are rear wheel, and we're assuming it takes 190 rwhp to push a Fox Body to 135 mph under optimum gearing conditions. Given those assumptions --- 135 mph X (the cube root of (your car's rwhp/190rwhp)) = top speed. If you plug in the math above (618 rwhp) the formula spits out 199 mph. So, if your supercharged ati fox body is putting down 450 rwhp, and it's geared properly, this would say top speed would be 179 mph. If you don't like the assumption that it takes 190 rwhp to hit 135mph, just change those numbers to whatever you believe and calculate away. But it's just playing games with numbers. Even if the math is right, it takes an EXTREMELY well prepared car to hit those kinds of top speeds. And the area where people can get into trouble the quickest is not having the tires, brakes and/or suspension to cope with the speed. And stock Fox bodies are inadequate in all 3 of those areas.
 
I'm not sure on this but even at 11 psi, with only a MAF to improve air flow throughout the rest of the engine that it could come anywhere near 450rwhp, in my uneducated opinion it wouldnt surpise me if that car is only in the low 300's.

I say 155 but it all depends on tire size, gearing, drag, how lowered the car may be etc