DHD 300-120 Duramax High Flow Manifold & Up Pipe Bundle 2001-2004 LB7

DHD's high flow manifold bundle increases exhaust air flow over 55% without any port modifications. Additional gains can be found in port matching and port blending. Our manifolds are cast from the same high Silca Iron that's become standard in the high flow manifold market. Included in the high flow bundle are our .120" wall thickness 304 stainless steel up pipes, featuring sleeved bellows and double welded pipe/flange connections.

Our manifolds swept back tapered inner diameter port design will accelerate exhaust gases to the turbine, lowering EGTS and making it easier for the turbo to spool quickly.

Features / Benefits:

Reduced Back pressure
Improve Fuel Economy
Lower EGT's and drive pressure
Quicker turbo spool up
1/8NPT Bungs in each manifold for EGT or Drive Pressure Sensor
Bundle Includes:

Right and Left Cast Manifolds
Right and Left .120" Wall Stainless Up Pipes
16 4340 Chromoly M10 12pt Manifold Bolts (Not cheap socket cap screws)
2x 1/8NPT Port Plugs
MLS Stainless Up Pipe Gasket Set (4 gaskets)
MLS Stainless Manifold Gasket set (2 gaskets)
12 12.9 M10 12pt Up Pipe Bolts
Want to make sure your getting EVERYTHING out of your investment. Considered purchasing our in house porting service. This service will port your manifolds to PPE oversize gaskets as well as gasket match the up pipe connection. You wont find a cheaper way to gain flow and lower EGT's! Use the menu above to add the option. Adding this option will add 1-3 business days to order processing.

Notes:

The passenger side up pipe is D shaped to allow for use with most aftermarket downpipes. However, slight modifications may need to be made to get the best fit depending on downpipe brand.
There is no EGR riser on the passenger side up-pipe. This kit is not a direct replacement for trucks equipped with EGR and should only be installed on pre-emission equipped trucks.