I ordered my mbrp to replace the flowmaster that's under the truck now. Still wondering about the power tube though. Does anyone make the downpipe from the turbo to the muffler for the 06 or is it not worth the trouble?

 

I can't say for 100% but you should have 4" from the turbo to the tail pipe. Unless you were saying you were going to run pipe from the turbo to the muffler and get rid of the cat??

As far as I know your 4" all the way, with a good muffler and everything else still on, your good to 500hp easy before you need a bigger system.