6.6 L Duramax LBZ
The LBZ replaced the LLY late in the 2006 model year and production continued through 2007. A large bump in output was seen with the introduction of the LBZ. Mechanically, the LBZ is very similar to the 2006 LLY model. The most significant difference between the LLY and LBZ is the computer controls. The LBZ features a much "wilder" tune, giving it a large increase in power horsepower and torque output.
6.6 L LBZ Specifications:
Configuration: |
90 degree V8 |
Displacement: |
403 cubic inches, 6.6 liters |
Compression Ratio: |
16.8:1 |
Bore: |
4.06 inches |
Stroke: |
3.90 inches |
Aspiration: |
- Variable geometry turbocharger (VGT) - Intercooler, air to air - 20 psi maximum boost pressure |
| Injection: | - Direct injection, high pressure Bosch common rail injection system, CP3 injection pump - Maximum 26,000 psi injection pressure - Seven hole injectors |
Valvetrain: |
OHV, 4 valves per cylinder |
Oil Capacity: |
10 quarts w/filter |
Weight: |
approx. 835 lbs |
Horsepower: |
360 hp @ 3,200 RPM |
Torque: |
650 lb-ft @ 1,600 RPM |
| Maximum Engine Speed: | 3,250 RPM |
| Emissions: | - Catalytic converter & exhaust gas recirculation system (EGR) |
6.6 L LBZ Features & Info:
- LBZ applications include the Chevrolet Silverado HD, GMC Sierra HD, Chevrolet Kodiak, GMC Topkick.
- Nicknamed the "hot rod" of Duramax's due to its performance potential in the aftermarket.
- More powerful tuning than the LLY boosts peak horsepower & torque considerably over the LLY, though the LLY & LBZ are mechanically very similar.
- Compression was lowered to 16.8:1 for the LBZ.
- Increased piston pin diamter bore & thicker connecting rod "I section" over previous generations.
- Injection pressure increased to 26,000 psi.