How to get atleast 400hp without using different engine and without using supercharger or turbo?

Question

i have a 99 mustang gt 5 speed and trying to reach atleast 400hp with putting a supercharger or turbo on and was wondering if someone coulld help me out as far as parts and cost

Answer 1

Need a bit more info. Like which engine. A rough budget would also help. You can spend several thousand if money is no object!

Answer 2

Ain't gonna happen.  That 4.6L 16v doesn't have the heads for it.

Answer 3

the only way to get CLOSE without heavy engine work, swap, supercharger or turbocharger would be too get a performance intake manifold, throttle body, exhaust, long tube headers, cold air intake, throttle body spacer, and maybe even a torque converter for the tranny. You WILL NOT make 400HP by any means, but its definitely a good horsepower increase. A 2500 stall torque converter, from a stopped launch, will slice close to 1 second off your 0-60 times...good luck!