I have a 2008 GT with a steeda CAI,Steeda throttle body spacer, Bassani offroad xPIPE, Flowmaster 40;s. SCT 93 Tune. Just put the xpipe on last week. Car sounds Horrible, alot of Rasp,throttle response is crappy and alot of crackling from the mufflers. I thought it was the tune but I redid it 5 times with a different one. ANYONE HELP PLEASE

 

O/R X + flows are famous for being raspy. With an o/r x you need a straight through muffler like stingers, magnapacks or bassani race.

 

the rasp is from the o/r x pipe.
the throttle response is from the tune.
so it ran fine with the other mods, minus the x pipe?

 

Ditto to all above - I put the stock mufflers back on after doing X and headers - still sounds aggressive but not nasty - I had the other Flowmasters - You might want to switch to O/R H pipe

 

Its the Throttle Body spacer.
Remove it at once.
Expensive paperweight.