well i got to looking around i think it is bully dog makes a inch down pipe

 

the whole system flows better... And if I remember correst teh evpandit has a 3.5" downpipe

Here is my Expandit install, I used a aftermarket 4" DP for a 2nd gen becasue teh turbo I'm running uses a 4" outlet.

https://www.dieselbombers.com/5-9l-r...its-turbo.html

 

exhaust is on my to do list

 

just ordered mine yesterday. i got the bully dog full 4" from the turbo back. the 3" outlet of the turbo is a restriction but 4" right from the turbo back should make a REAL nice sounding system. expandit specs say the DP is actually 3". i priced the expandit and the bully dog; they're actually pretty close in price and the sponsors set me up real nice

 

I though teh bully dog had teh same DP as the Expandit (I actually think they are teh exact same kit)

 

i bought the bully dog exhaust from summit. it didn't come with a down pipe. so i got a down pipe from sourceautomotive.com i ended up spending about $600 for 4" from the turbo back. and i would never let the 3" down pipe on, its very restrictive on our trucks. what with all the bad bends and kinks in it.