The GT500 will need less to hold the same power. If you really want that much power in a S197, it's the best option.

 

True true. Anybody know what stock RWHP on a 500 is?

 

Which one?

 

Here's the info on the 2007 GT500. They've only gotten better since then.
http://www.modularfords.com/f128/sum...results-59181/

 

Well dang, i don't know what I'm gonna do. Might just get long tubes and gears and shut up.

 

You can get 450rwhp for as little as $3500 total. Not with headers and cams has to be FI. Check here.

 

But you also need to remember your chance of blowing sh*t up is gonna be much greater. There was an article on muscle mustangs or their sister site about what breaks on mustangs... It would be a good idea to work on those bits if your going to start getting in the upper 400s at the rwhp level because it just starts breaking down and will eventually need to be replaced. That's the thing with adding so much horsepower, you need to supplement it with parts that can support it.