is there a down pipe that is bigger i can get to put on my duramax? and the other problem i have is i already have an exhaust system on so i guess i will need to cut the top off to match the down pipe to the exhasut? i have the banks monster exhaust.

so no one knows

I was under the impression that the only down pipes from the turbo are for aftermarket turbo setups. I have no clue why nobody has made one yet???? Maybe somebody finaly has I have no clue

I believe you can go to a 6", 5" for sure becuase thats what my down pipe is.

Just for clarification...

the pipe you all mean is actually the front pipe.. where the cat is. The pipe that is connected to the turbo and goes down and connects to the front pipe is called the "down pipe". The front pipe can be replaced with a catless one in 4", 5"..etc...

the reason there is no aftermarket true "down pipe" is becuase there is no room for one. There is only a couple of inches between the turbo and the firewall and the down pipe is crushed and bent to fit in there already.

also you shoudln't have to cut anything.. if you have a catback from the 4 bolt flange it will bolt up to the new front pipe as well.

Not to bash anyones thoughts but I believe Borla makes a 4" down pipe..I called Scottys and asked them if they put a 5" down pipe on my truck. He checked and there is a 4" downpipe, 5" all the way back (no cat no muffler) a "Y" pipe and 2 6" chrome tips.

there are no aftermarket "down pipes".. the front pipe can be replaced with 4" borla, MBRP, banks, etc.... there just is no room for any "true" down pipe on our trucks.

just trying to correct the common mistake of a down pipe and front pipe so there is no confusion on terms.

the pipe with the CAT on it is the FRONT pipe, it bolts to the DOWN pipe which goes to the turbo housing. The DOWN pipe cannot be upgraded at this time(physically no room). The FRONT pipe and all pipes after it can be increased from the stock 3.5" to 4", 5", and maybe even 6"...

Here is mine:

Thank you for clearing that up. I kept looking at all of these brands claiming it was a turbo back, with down pipe, etc. I just got the truck and havn't worked on it or looked at it too much. I was checking the tranny fluid after changing the allison spin on. I was trying to figure out how the hell you could change the down pipe to a 4" and make it fit and better yet be able to remove the old one and put the new one on.
So nobody makes a bigger down pipe for the duamax? So all of the places claiming a turbo back exhaust or include the down pipe are really full of ****.

Well truthfully, that discharge is part of the turbo...so they aren't lying, it is "turbo-back exhaust". Typically enlarging that part of the turbo has little effect since the gasses there are still very hot and moving quickly.

So nobody makes a bigger down pipe for the duamax?

No...see reply number 5 and 7 above.

So all of the places claiming a turbo back exhaust or include the down pipe are really full of ****.

Its just marketing...99% of the systems that say "including down pipe" actually mean the front pipe when speaking of the Duramax.

there are no aftermarket "down pipes".. .... there just is no room for any "true" down pipe on our trucks.

The DOWN pipe cannot be upgraded at this time(physically no room).

Just need to clear up a few things from the above statement. There are some aftermarket downpipes that bolt to the turbo (just not for sale yet) and yes, they do fit. They will be released by the end of the year for the LB7's with the LLY's shortly there after. You will need to modify or replace your front pipe as the new downpipe has a true 4" connection. :D

Just need to clear up a few things from the above statement. There are some aftermarket downpipes that bolt to the turbo (just not for sale yet) and yes, they do fit. They will be released by the end of the year for the LB7's with the LLY's shortly there after. You will need to modify or replace your front pipe as the new downpipe has a true 4" connection. :D

sweet, thanks for the info!!! I did say in one of the first posts.."to my knowledge".. LOL..

how the hek are they going to fit it in that tiny space between the turbo and the firewall??

Sounds like somebody needs to make a 4" front pipe to connect to the new 4" downpipe.
Or somebody besides ATS will come out with an aftermarket turbo & that doesn't blow up when fuel is put to it. Wasn't Garrett supposed to be coming out with one?

Good things come to those who wait.

It may sound stupid cause I haven't done my tranny yet, very soon now. I can wait on getting something good like that, as long as it's out by spring, wouldn't mind getting one & kicking some ATS butt with it.

Call Borla (877-462-6752), They make a 4" system COMPLETE! Thats down pipe off the turbo, front pipe, cat or no cat, muffler or no muffler, and from the muffler back.

It DOES NOT INCLUDE THE ACTUAL DOWNPIPE There is no true downpipe available yet over the counter. Sounds like TTS will be the first when they releas thiers.

Look at my post about Borlas 4" down pipe...I am gonna post a few pics to prove it. let me take the pic...one sec and the post will be up.

It DOES NOT INCLUDE THE ACTUAL DOWNPIPE There is no true downpipe available yet over the counter. Sounds like TTS will be the first when they releas thiers.


this is what I have been trying to explain.. LOL..