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Punisher Performance Reaper Tuner for 2001-2004 GM Duramax LB7

Part# Reaper-DuramaxLB7
$699.00 Now $665.00
Qualifies for FREE SHIPPING

AVAILABILITY: Ships from Manufacturer


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Product Description


The Reaper programmer from Punisher Performance utilizes the EFI-ILive Autocal platform to give you the best custom tuning options in an easy to use handheld programmer. Punisher Performance has spent hundreds of hours adjusting and fine-tuning these programs to ensure that your Duramax LB7 will see the best and safest gains in power, torque and fuel mileage. These tunes are appropriate for Duramax LB7 diesels with stock engines and transmissions. There are five different adjustable power levels pre-programmed on the Reaper so you can choose the tune that meets your specific needs. Adjustment is made via an included DSP5 switch.

Key Features

  • Comes Programmed with 5 Power Levels
  • Includes 5 Position Switch
  • Reads and Clears Diagnostic Trouble Codes
  • Scans and Logs Data
  • Performance Exhaust System Strongly Recommended



Reaper Duramax LB7 Power Levels

  • Optimized Stock
  • Economy 50 HP Gain
  • Towing 65 HP Gain
  • Mild Street 90 HP Gain
  • Hot Street 120 HP Gain

The Reaper can be configured to tune everything from a stock Duramax, to a full blown competition race truck.If you’re planning on doing some upgrades to your Duramax in the future, Punisher Performance has you covered. Anytime you add performance parts that require a re-tune, they are glad to take care of it for you. The Reaper can optimize any combination of aftermarket parts, so you’re never stuck with a pre-canned set of tunes. The Reaper allows you to log-real time data so that Punisher Performance can view the information and write new tunes for you remotely, and all information is exchanged via email!

DSP 5 Position Program Control Switch



One of the cool features of EFI-Live tuning is that a switch is available that will allow you to change between the five different tunes any time you want. As an added value, your Reaper Autocal tuner will come with this clean and simple DSP5 position switch at no extra cost. The switch has a simple two wire installation, and the rotary knob mounts easily out of sight, or to your dash for easy reach. Switch Installation Instructions are provided.