Anyone know the exhaust pipe size on the 04/05 scabs with a 5.4? I believe that it is 2.25" My plan is to split the system into a dual setup just after the cats, and run a pair of stainless flowmaster 40's with dual tips, all in the stock size.

 

its 2.5"

 

I cut out the exhaust from the right side the FX4 has a cat on each bank I ran 2.50 pipes out each side rear with rolled stainless tips NO mufflers Loud when you first start it but quiets down quickly after baffles in Cats get hot I myself had Flowmasters but dumped them Truck only gets loud when I TROMP on it Look at Magnaflows if you want mufflers

 

Thanks for your suggestion, but I'll stick to flowmasters, I like thier sound