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Results in torque and power gains across the full operating rpm range, starting right off idle and marching to the shift point in each gear. Derringer is dyno calibrated to use multiple data inputs such as throttle position, rpm, vehicle speed, AFR, knock, coolant temperature, and EGT, just like your engine's ECM. It actively and safely optimizes calibrations in real-time thanks to its OBD-II connectivity. No competitive tuner does that.
Derringer has 6 levels, adjustable on-the-fly using the iDash. Level 6 produces best-in-class performance. Level 3 is designed for work use and has a great mid-range feel. When running Level 3 with a loaded truck and/or pulling a trailer, your on-ramp merging speeds and passing times are greatly improved.
The electronics are enclosed in a compact housing which is easily concealed and communicates with other Banks devices such as our iDash DataMonster, iDash SuperGauge, and PedalMonster throttle booster. The Derringer connects in line with your truck's engine sensors. But unlike other tuners, it also connects to the vehicle's OBD-II diagnostic bus.
ActiveSafety health monitoring circuitry keeps an eye on the vehicle and the module itself. It checks its health 100 times a second. If it detects an issue, the Derringer instantly bypasses itself, sets a device diagnostic code, and seamlessly returns the truck to stock power. Plus, Derringer's special coolant temp monitoring prevents power addition when the engine is too cold or overheated. The Derringer also auto-adjusts power if knock occurs due to bad fuel. Maximum safe power is all automatic with a Derringer — you just choose your preferred power level and enjoy the ride.
Emissions Compliant: D-161-120
US Patent # 7,593,808 & # 7,254,477
The Derringer L5P tuner is the only option you should be plugging into your truck. The other guys claim big numbers but simply don't deliver! We tested every other tuner on the same dyno, same day, same weather conditions, and with the same technician. There’s only so much you can do by just intercepting the fuel rail pressure sensor. That’s where all the others fall short. The Derringer is the only tuner that actually utilizes your truck’s ECM to make intelligent calculations. Hundreds of man-hours went into Derringer's development and the results are nothing short of impressive.







NOTE: Dr. Performance and Stealth both use the same box.
Test Vehicle: 2017 Chevrolet Silverado 3500 Dually 6.6L Duramax L5P. Factory intake and exhaust. All tests run on the same truck, same day, same conditions. Tested on Mustang DYNO, 10-second sweep.
AutoRate® Dynamic Tuning
Unlike the fixed tuning used by others, the Derringer calibration is continuously adjusting to provide you the peak possible performance under every driving condition. By utilizing the power of the OBD-II data, the tuner intelligently fine-tunes its calibration on the fly without you having to change its power level.
TransCommand® Active Transmission Safety System
In addition to AutoRate Adaptive Tuning, the Derringer utilizes key engine and transmission parameters to enhance shift performance and improve the longevity of your transmission. Because the competitors lack the essential OBD-II data, they always add power at wide-open throttle—no matter what! This can cause excessive transmission slip, torque converter clutch slip, and even 100+ HP engine derates in order for the transmission to complete the shift. This harms the overall performance and degrades your transmission. The Derringer is meticulously calibrated and extensively tested to properly modulate power during shifting, optimizing performance and safety.
ActiveSafety® Health Monitoring
The Derringer is the only tuner on the market to include ‘Active Safety’ health monitoring circuitry. This active failsafe system utilizes bypass relays to smoothly transition your vehicle to stock power levels in the event of any trouble signs in the Derringer. The system constantly monitors various parameters over 250 times a second to ensure that everything is operating as it should. If any competitive tuners lose power or fail in any way, they will instantly trigger a “limp home” mode where all power is lost and the vehicle dangerously slows to a crawl. If the same fault condition occurs to the Derringer it will gracefully remove its additional power and return to stock power levels without a hitch.
Additional Features
Additional Features with iDash DataMonster or SuperGauge

Stock L5P Turbo Limits
The factory turbo is done at 505 flywheel hp, that’s a gain of 60 horsepower. Above that point, the turbine drive pressure increases dramatically as does EGT and no more boost is available to safely add horsepower. Anyone who claims to deliver more doesn’t understand this engine.
The Derringer L5P is the most sophisticated inline tuner available. We hope you have as much fun driving with it as we did making it.
Fast delivery services available:
30-day return window. Tags must be intact.
Manufacturer defects return free. Other returns subject to $3 fee.