so whenever i smash the pedal (not really pedal to the metal) and revs up past 4.5k im hearing a loud hissing sound on the bottom and my car wont speed up, could be a exhaust leak?

 

it's possible, here's how i found mine: pull the car up on ramps or jack it up, ramps are safer IMO, wait for the car to be completly cool, spray some soapy water on the exhaust piping in the area you here the noise, start the car, you should see some bubbles. i know it sounds dumb but it worked for me. Also, while its running sometimes you can feel the exhaust leaking out if you run you hand somewhat close to the piping after its been sitting for a while and you jsut start it up.

 

thanks bro and its not dumb any help i can get is great bro appreciated

 

You could also Seafoam it and see where it smokes from.

 

it appears its not on the bottom of my car but under the hood
so ima test it out tomorrow

 

might be your header

 

thanks for the input guys but i found whats causing it
my intake snorkel melted on this hot weather and became soft not its kinda closing in so when i try to gun it the intake struggles to suck air and im losing power in mid range but since we took it off now the car is running smooth and fine