Justin- You can get 4" pipe from any of places listed in earlier posts, or look in your local yellow pages under "truck parts". Some truck parts places will take anybody's money as long as it's green, but some will only deal with a shop.

 

Hey all I just wanted to clear up why I made the box for stacks .well, I have read in post that the pipe in the bed and yed under the bed has a worse DRONE than the tube. My truck is as quiet IN THE CAB as it was when it was with the STOCK muffler I don't have to yell at my passenger.my opinon.

 

Just to note... I wasnt trying to BELITTLE ANYONES work, I was just simply saying that running straight into a piece of square tubing, creating a "T" , DOES NOT flow as well as making a smooth transition into a "Y" would. Not to mention the back up that would be made with the 3 right angles (one "T" and 2 sharp 90s).
Exhaust flows very similar to water and you dont see much (high flow) water running through square tubing. You do however see high flow water running through round pipe and making smooth "corners" (90's) and even better 45's.
Having the Y under the bed creates NO drone in my truck and a very pleasant ride (with the windows up ) .
I meant no disrespect on anyones work. I was just letting everyone know that square tubing is not the best way to go if flow is a major concern and that, it IS possible to go 4" over the tank.
Scott

 

Can you go 4" over the tank with a 1st gen? I don't usually haul stuff in the bed.