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L8T with 6L80/6L90 Harness Package

L8T Engine

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L8T with 6L80/6L90 Harness Package

$0.00
Choose your options:
Fuel System:
Add O2 Sensors?:
Add 6L80/90 Tap Shifter?:
Add NSS?:
Gear Ratio/Tire(required):
Emissions Wiring(required):
Front End Drive(required):
Examples are Holley, Wegner, CVF Racing, Drive Junky, etc.
6L Reverse CAN relay:
Product Code: HP-L8T-6L80
Harness package for use with the 6.6L L8T engine with 6L80/6L90 transmission. Includes the following:

L8T standalone wiring harness
Programmed ECM with base calibration (Fine tuning may be required locally)
Reprogram YOUR supplied T43 TCM (You must ship us your TCM after placing the order)
Front oxygen sensors
4-wire fuel rail pressure sensor
MAF sensor with bung
ETC pedal


GM's 6.6 Engine with 401 horsepower and 464 lb.-ft of torque. A nice addition for the direct injected engine family seen in GM's 2500 and 3500 trucks.

See link here for GDI information options