What exhaust set up did you have prior to the single 4" and do you have any dyno or track performance to show what the change did?

 

I had a single 3" and went to 4"

Lost 1-1.25lb boost and my back pressure went from 10-12lb to 0
No direct comparison as I had not been to track for a couple years.

It without a doubt increased topend pull, my 3" exhaust sounded like a huge air leak at wo.

 

Unfortunately I don't have anything to compare either. I went 4" before I even knew for sure I needed to and I haven't looked back.

 

I haven't researched it much, but is there an easy 4" exhaust setup or has everyone went custom? I've got a 2000 RCSB. What's the best/affordable solution?

 

Mine is MBRP for a duramax, it was a directly bolt in.

 

MBRP is very affordable.
My rcsb uses it. I added 1 hanger to help hold mid line.
4" is a close fit in some areas.

 

I only have 4 inch over the axle and tail pipe but going from a pos 3 inch exhaust to a real setup with good muffler and tail pipe made a world of difference on my truck.

And it looks badass. =]

https://www.performancetrucks.net/fo...-after-524031/

 

The issue us non turbo guys have is that most diesel exhaust systems are incredibly loud without an exhaust snail in line... The MBRP will be no exception. You will likely have to add a second muffler in line.

 

Correct. The little diesel muffler it comes with is useless.

Mine was replaced with a massive magnaflow 30" diesel muffler

 

My MBRP came with a huge muffler.
Besides NA / blower with 4" is a waste of money.