[Tom Vaught]

Pic #1, post #28, WHY DO YOU HAVE THAT MERGE PIPE INSTALLED IN THE OPPOSITE DIRECTION FROM WHAT IT WAS DESIGNED TO BE RUN AT. You come off of the single pipe, REDUCE the area of the pipe, then split the pipe into two pipes and expect that to flow some exhaust? IMO The actual flow area at that point looks like it is less than ONE of the dual pipes area farther down stream.

Tom V.

[er455]

Originally Posted by Tom Vaught

Pic #1, post #28, WHY DO YOU HAVE THAT MERGE PIPE INSTALLED IN THE OPPOSITE DIRECTION FROM WHAT IT WAS DESIGNED TO BE RUN AT. You come off of the single pipe, REDUCE the area of the pipe, then split the pipe into two pipes and expect that to flow some exhaust? IMO The actual flow area at that point looks like it is less than ONE of the dual pipes area farther down stream.

Tom V.

How else can you run dual exhaust without splitting it somewhere ? This is the exact setup all the Buick grand nationals run well into the 9,s I am going from 3.5 “ merge pipe to dual 3” pipes , I would like to have a 4” downpipe but not sure I can fit it ..

[Boostedbird]

Originally Posted by er455

How else can you run dual exhaust without splitting it somewhere ? This is the exact setup all the Buick grand nationals run well into the 9,s I am going from 3.5 “ merge pipe to dual 3” pipes , I would like to have a 4” downpipe but not sure I can fit it ..

Tom's right, that merge piece is absolutely killing any flow that you had. You need a larger downpipe, a merge something like the one in the picture or a custom one, and probably an electric cut out or a Loud Valve on the downpipe.
You asked about my exhaust. I have a 5" downpipe that runs from the turbo down to about the rear of the transmission where I smoothly transitioned down to 4". It stays 4" back to the bumper where my 4" muffler is. The muffler is a Dynamax Ultra Flow. It's straight through and pretty much just changes the sound a little. I'm either gonna put a 4" Loud Valve dump on the downpipe up front or run a second 4" pipe from the 5" to 4" transition.

[er455]

Originally Posted by Boostedbird

Tom's right, that merge piece is absolutely killing any flow that you had. You need a larger downpipe, a merge something like the one in the picture or a custom one, and probably an electric cut out or a Loud Valve on the downpipe.
You asked about my exhaust. I have a 5" downpipe that runs from the turbo down to about the rear of the transmission where I smoothly transitioned down to 4". It stays 4" back to the bumper where my 4" muffler is. The muffler is a Dynamax Ultra Flow. It's straight through and pretty much just changes the sound a little. I'm either gonna put a 4" Loud Valve dump on the downpipe up front or run a second 4" pipe from the 5" to 4" transition.

Ok maybe my pics are not showing what I have the merge pipe looks like the one you posted here is a pic of what’s on my car ...