Our tuning backlog is longer than normal going into October and additional delays should be expected. Please email with any questions.


THE BEAST DS4 Injection Pump

Quadstar Tuning LLC

  • $2,500.00



Meet the ONLY high output DS4 injection pump available for 6.5L turbo diesel applications.  Proven anywhere from stock power to 452 HP at the wheels, this pump is ready to deliver. We've been testing and selling this pump via custom order for the past 3 years now to get it where it is today.

Everything on these pumps is 100% new from the housing to the electronics.  They utilize larger cam ring lobes and other internal modifications that are required to support the fuel flow.

Some of the DYNO PROVEN tunes we can do to go with this pump:

  • 150 HP Stock output
    • Stock HO 6.5L trucks average 150-165 HP to the wheels on a loaded dyno run
  • 265 HP Daily Towing
    • 265 wheel horsepower is +100 over stock vs the latest 1999 K3500 tune from the factory
    • This tune consistently gets over 20mpg even in a Suburban or K3500 dually
  • 275 HP Daily Driver
  • 361 HP Daily Performance
  • 390 HP Daily Performance + Throttle Boost
  • 414 HP Daily Performance
  • 452 HP Max Effort
  • Or anywhere in between. That's the beauty of an EFI DS4 pump : ). Switchable tuning equipped vehicles can also flip between all levels on the fly!

Why is this pump one-of-a-kind?

  • There has never been a proven high output DS4 pump available before this one
  • It's been daily driven by us and a handful of customers for the past few years Unlike other higher fueling 6.5L builds, you can drive your truck like normal and take it wherever you want to go
    • Road trip with family in a Suburban? No problem
    • Tow or Haul whenever you want? No problem
    • Take your buddy for a ride in the stock power tune then flip the switch and watch their jaw drop? "A 6.5 Can't do that!" No problem!
  • Unlike modified mechanical pumps, the computer can control maximum fuel rate commands at lower RPM when you put your foot to the floor. Over fueling at low RPM is not a concern.
  • Cold weather starting, hot weather starting, lower compression? It doesn't care. These are guaranteed to start easier than any pump you've ever ran.  
  • Fuel mileage - May be hard to believe but it can beat a stock pump on fuel mileage due to a much more efficient injection event. It's also capable much of worse in a tune that'll let it eat!

What you NEED to run this pump:

  • Entirely updated fuel system. 1/2" Suction line from fuel tank and 3/8" pressure out of a minimum 100gph lift pump. You can NOT cut corners on fuel supply and filtration. You want to run as close to 10 psi inlet fuel pressure as possible at all times and never starve it of fuel.
  • Our 3/8" DS4 fuel inlet upgrade kit. Stock fuel supply lines and filters should not be anywhere near your truck if you are considering this pump
  • Turbocharger, exhaust, and intake upgrades. Super 54 or Super 60 turbo. Super 60 required above 300 HP
  • Marine Style Injectors highly recommended above 300 HP
  • Fluidampr harmonic balancer
  • Head studs and/or O-rings depending on HP level
  • New engine wiring harness, clean ground points and good battery cables. Worn connections to things like the optic sensor and PMD will cause extra load and damage to electrical components
  • Remote PMD with NEW extension harness. We install a block off plate to both identify the pump and prevent installation of a PMD in the stock location
  • Matching tuning
  • Intercooling - At some point, you need to add an intercooler. Physics tells us that you need to cool the air charge. Regardless of what turbo you have, it makes heat when you compress air.
  • You need to know how to properly set timing (TDCO) to factory spec with this pump.  It will not tolerate an incomplete install or any skipped steps and we do not recommend advancing base timing past factory spec with it. The tuning will handle the dynamic timing curve adjustments.

Custom tuning is required to match this pump. It will NOT run properly with stock or existing tuning.  We are the only company that can tune this pump for your truck.

Warranty: This performance application pump carries a 90 day replacement guarantee. Outside of 90 days, we will require a full inspection/analysis to look for fuel contamination or damaged caused by wiring issues.  There is no longevity guarantee above the 390 HP level but we have no concerns with longevity vs a stock pump at or below 390 HP.

All runs were performed on a loaded Dynocom 15000 dual eddy brake dyno that anyone can go strap their truck onto as it's actively in service and available for booking. Standard correction factor is shown for those who want to run against them for comparison.