take cat off, its clogged might just clean it out idk yet.

run 3in from the collector/ Y pipe to a flowmaster 40. its a 2 1/4 in/out im gonna cut down the inlet to be flush with the 3in.

then 2 1/4 out about a ft. then dump

doin this on the very cheap side got the muffler and pipe for free

any ideas on wtf this is gonna sound like

 

ya here is a vid of when i have shorty headers no catto ypipe to flowmaster 40 with downflows.. exactly how u just listed with a 5.9 also this is when i seafoamed my truck so dont mind the smoke..

http://www.youtube.com/watch?v=RAOigL6bc9A

 

here is mine...i have summit racing shorty headers true dualed into 2 1/4 inch piping back into two jones mufflers out the back at about 45 degree angle 3 1/2 inch tips

http://www.youtube.com/watch?v=P4EFF5Zrwuw