i'm about to run a "true dual" setup. get pipes to go from my cats to a dual in/our magnaflow SS muffler and dual out the back. any input? Not sure of 2.5 or 3''

worth it over a gibson catback (single in/out, 3'')? Just wait till pace setter has 4x4 headers and do it then?

 

2.5 inch should be plenty for you for a true dual setup. Unless you have around 500hp and up in your truck then 3" is too big. Let us know how is sounds after the magnaflows are on.
When you get long tubes then you will need to fix the front part of the exhaust but it all should work just fine together.
For welding SS to aluminized use 309 rod!

 

Use 309L

 

2.5 will be plenty.

 

I just went with a new exhaust setup. Pacesetter LT's, removed cats,all new mandrel 2.5" tubing, and a Magnaflow dual in/dual out stainless(5x11 22" the biggest one/internal x-pipe) muffler w/turndowns and I am extremly happy with it. Obsiously I was expecting some nice power gains going from stock exhaust except a Flowmaster Muffler and I got the gains but it sounds good. Its loud and thats with the biggest muffler(cant imaging the 4x9) but sounds healthy. I know Im running a different motor and no cats but I think its a good choice for you!

 

Hey Tigerfan, who did your exhaust work for ya? My exhaust shop was wiped out by Katrina and in need of some work done on the new truck. Thanks