What tires grip ?

Ray - tires are sized uniformly and the numbers are consistent. Any 205 section tire is 205mm wide from sidewall to sidewall. The aspect ratio (60 series, 50 series, etc.) when multiplied by the section width tells you how tall the sidewall is. So, a 205/60/15 tire is 205mm from sidewall to sidewall; the sidewall height is .6X205=123mm which is 4.8". So the overall height of that tire is 2Xthe sidewall height+the diameter of the wheel - 2X4.8+15=24.7". You can use that math to calculate height of any tire. The taller the tire, the more it effectively reduces your rear gear ratio - so a taller tire will help you lengthen the gear in your car.

While there may be minor differences from maker to maker, a 205 section tire is noticeably narrower than a 225 section tire. And you need as much tire on the back as you can get. As mentioned earlier, no matter what you put on there, with 500 lb-ft of torque available, you're gonna be able to smoke the tires at will no matter what size they are.
 
400HP + 500 lb-ft + cheap tires = ???? I'll let everyone else complete the equation. Probably the single most important AND overlooked performance enhancement available to most cars is a decent set of performance tires. They are the ONLY connection between all those wonderful engine/driveline/suspension/braking mods we do and the pavement. And yet they are consistently overlooked. The most expensive aren't always the best, but cheap tires are almost always unpleasant, on so many levels.
 
So what would be a good size then, I thought 45.50, etc was the width guess not, I got 245's right now so for more width I'd need to go to a 255 or bigger then right, the 45,50,etc in the height of the tire from the rim basicaly then right, what about hoosiers I heard they made some good gripping tires, guess nittos are out of the question with an only available width of 205 that would be rediculouse skinny then right ?
 
Ray - from my previous posts here --

"You're gonna need as much wheel and tire under that back of that thing as you can get. 255's minimum. And a tire that wide needs to be mounted on at least an 8" wide wheel. Seems like some folks get 275's under the rear - that needs a 9" wide wheel. Putting the wider tire on the stock narrower wheel somewhat defeats the purpose as mounting one that way keeps all the tread from being able to contact the ground."

"Also, you may want to jump into this thread and chat with these guys - they seem to know a thing or two about getting big rubber under the back of a fox (10" wide wheels with a 6.5" backspace).

http://forums.stangnet.com/showthread.php?t=519436 "

The aspect ratio (the 45, 50, etc, number) is NOT "the height of the tire from the rim basicaly". It's a percentage (45 means 45% or .45) which when multiplied times the section width (205, 225, etc) gives you the height of the sidewall.