Have a 97 with the 5.4, took off muffler and welded on a piece of straight pipe, sounds decent but I want it to cackle and "pop" more. Stock pipe is 2.5thinking about putting a 2.5 to 2.0 reducer on with more straight pipe a 45' bend and have it exit out before the rear tire with a 2.0 inlet tip. What do you think? will 2.5 to 2.0 hurt my performance, or will it make it cackle more like I want?

 

How many cats do you have?

 

it'll most likely do both. Going a size smaller at the back isn't healthy for performance.

Get 2.25" true duals straights installed and it will crackle and pop much more.