i sintalled my jdm header and highflow cat and got my piping resized to to 2 1/2 but icant stand the raspy sound it makes would a resonator give a lower tone if so where could i get a hold of nice aftermarket one

 

I've heard good things about the Magnaflow Resonators.

They will get rid of any raspiness and won't sacrifice any performance. I'm sure your local muffler shop can get ahold of them. If not you can email me and/or check out magnaflow.com.
HTH
M