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Racing Exhaust Manifold

Buy Now For $725.00

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Racing Exhaust Manifold

Buy Now For $725.00

Add To Cart
Banks exhaust manifold kit
Ported outlets
Ported inlets
Plugs shown
Plugs shown
Gasket comparison
Shown installed

Racing Exhaust Manifold

Pure Race Capability
Race Ported 1.77 x 1.58 Inlet, Ported 2.12 Outlet
For Duramax 6.6L LBZ/LMM/LML
Limited Inventory
MSRP $805.56


Free Shipping on orders over $250 (48 Contiguous US)*

Part of the Banks Racing line. The best purpose-built cast exhaust manifolds created for racing the Duramax engine. Provides tremendous flow and uniform air distribution. 

For Race Applications only

Fitment Note

Does not fit stock or aftermarket up-pipes. Flanges included for the fabrication of custom up-pipes. Hardware not included.

Key Features

  • Banks' Precision Port Alignment System allows the manifold to expand & contract without shrouding ports
  • Proprietary bolt pattern on outlets for ease of bolt installatio, includes gaskets
  • Designed and perfected in computer simulations for maximum drive pressure
  • Can be mounted stock position or reversed towards the front
  • Outlet Flanges sized for 2.25" .06 wall tubing
  • CNC ported to fit aftermarket big port heads
  • Inlets are Race Ported to 1.77" x 1.58"
  • High silicon moly for extreme temps
  • Outlet Bolts M10x1.5 (not included)
  • Outlet is 2.125" Race Ported
  • We recommend using ARP 762-1008 SS Hex M10x1.5 fasteners to the head (not included)
  • Does NOT work with OEM or aftermarket up-pipes (Flanges included for fabrication of custom up-pipes)


If you are a racer and have an LBZ-LML 6.6L Duramax, Gale Banks Engineering offers The best cast Duramax manifold ever. Lay the power down with Banks Big Hoss Duramax Exhaust Manifolds!

For high performance, getting the exhaust gasses out of an engine is just as important as getting air into it. These race-ready, high-flow manifolds were designed by Banks for the ultimate in fit and performance.

For use at sanctioned race events only

Questions? Contact Support

Duramax Exhaust Manifolds Comparison

A) Port size 39mm wide x 35mm high, Area = 1,320mm2

B) Inadequate cross-section for high output

C) Poor entry conditions, No port runner blend to the main runner

D) Exhaust runner choke point

E) Exhaust port choke point

F) Outlet size diameter = 45mm, Area = 1,590mm2

E) Special high-temp material

Comments: Okay for lower power.

  • Poor flow dynamics
  • Unequal cylinder to cylinder back pressures
  • Inlet & outlet undersized
  • Up pipes are small & restrictive

A) Port size 37mm wide x 36mm high, Area = 1,295mm2

B) Inadequate cross-section for high output

C) Inadequate cross-section

D) Inadequate cross-section

E) Reverse flow

F) Outlet size diameter = 46mm, Area = 1,161mm2

Comments: Flawed & obsolete design

  • Port size smaller than stock and not sufficient for high performance
  • Rear port causes excessive turbulence
  • Outlet smaller than stock
  • Will not fit currently ported heads
  • Up pipes restrictive & mild steel in bends

A) Port size 44mm wide x 35mm high, Area = 1,512mm2

B) Chokepoint, 19% smaller than the port inlet

C) Restriction/chokepoint

D) Chokepoint

E) Chokepoint

F) Choked port 16% smaller than the inlet port

G) Outlet size diameter = 48mm, Area = 1,832mm2

E) Special high-temp material

Comments: Very crude & obsolete

  • Chokepoints cause inconsistent flow velocity reducing flow potential
  • Ports not high enough or wide enough for current ported heads
  • Up pipes restrictive and mild steel will fail quickly in any performance situation

A) Port size 45mm wide x 40mm high, Area = 1,745mm2 (Largest in industry)

B) Increasing streamlined cross-section

C) Consistent flow dynamics to port

D) Outlet size diameter = 54mm, Area = 2,290mm2 (Largest in industry)

E) Special high-temp material

Comments: The best cast Duramax manifold ever.

  • Exceptional constant flow velocity
  • Ports fit the largest CNC race heads
  • Equal port to port pressure balance
  • Computational Flow Dynamics, CFD, confirmed design
  • Supplied with Banks/Cometic big port gaskets
  • Outlet area matched T6 flange area
  • Special proprietary high-temp/high-strength alloy