KC Whistler Stage 2 Drop-In Turbo - 6.7L Powerstroke 2011-2019

The KC Whistler Stage 2 (PN 300870) is a drop-in performance turbo for the 2015-2019 Ford F-250 and F-350 6.7L Powerstroke. It features a ported KC compressor cover, upgraded billet 64mm compressor wheel, and a larger 10-blade high-flow turbine wheel - delivering the classic 2003-style turbo whistle along with more flow than the Stage 1. Built for hot street driving, daily use, and occasional light towing. Not the right choice if heavy towing is the primary use.

Stage 1, Stage 2, or Stage 3 - Which One Fits Your Use

The Whistler lineup covers three distinct use cases. The Stage 1 is built for trucks that tow heavily on a regular basis - it prioritizes low-end response and sustained load handling over outright peak flow. The Stage 2 sits in the middle: more compressor flow than the Stage 1 through the billet 64mm wheel and larger 10-blade turbine, making it the strongest choice for street performance, daily driving, and occasional light towing where the goal is more power and quicker spool. The Stage 3 is built for heavily modified trucks that need maximum flow beyond what the Stage 2 supports.

The Stage 2 also needs a healthy fueling system to reach its full potential. A weak or failing CP4 will limit what this turbo can do - the additional flow headroom only pays off when the fuel side can keep up with it. This is the right turbo for a performance-focused street and light-use 6.7L build with fueling to match - not for a primary work truck pulling heavy loads, and not for a stock-fuel build chasing maximum output.

Fitment and Required Install Kits by Year

The KC Whistler Stage 2 is a direct drop-in for 2017-2019 6.7L Powerstroke trucks. Earlier model years require additional hardware:

• 2017-2019 F-250 / F-350 6.7L Powerstroke - 100% drop-in ready, no additional kit needed
• 2015-2016 F-250 / F-350 6.7L Powerstroke - requires the pedestal conversion kit
• 2011-2014 F-250 / F-350 6.7L Powerstroke - requires the Retro Fit Kit
• 2011-2016 Cab & Chassis 6.7L Powerstroke - requires the Retro Fit Kit

KC Whistler Stage 2 Features

• Ported KC compressor cover
• Upgraded billet 64mm compressor wheel
• Upgraded 10-blade high-flow turbine wheel
• 6.0-style 10-blade turbo whistle
• Improved boost control
• Cooler EGTs
• Quick spool up
• 100% drop-in ready (2017-2019 direct; earlier years see fitment section above)

Exhaust Brake Compatibility

The OEM exhaust brake feature will be retained if the vehicle's calibration supports it. However, some aftermarket exhaust brake brands have known clearance issues that can cause the brake to hinder performance, contact the turbine wheel, or create other problems. Exhaust brakes work by closing a flapper valve to create extreme back pressure, which puts additional stress on the turbo and motor. KC does not recommend the use of exhaust brakes with this turbo.

Avoid These Common Mistakes

• Installing on a 2015-2016 truck without the pedestal conversion kit - the turbo will not install correctly without it
• Ordering for a 2011-2014 or 2011-2016 Cab & Chassis truck without first sourcing the Retro Fit Kit
• Choosing the Stage 2 for a primary heavy-towing application - the Stage 1 is the correct choice for that use
• Installing with a weak or failing CP4 - the Stage 2 needs healthy fueling to reach its full potential
• Ordering to a CA or CO address - this turbo cannot be shipped to those states

Before You Order

• Truck is a 2015-2019 Ford F-250 or F-350 6.7L Powerstroke (non-CA / non-CO)
• Primary use is street performance or light towing - not heavy towing
• CP4 or fueling system is healthy or upgraded to support Stage 2 flow
• Install kit requirement confirmed by model year (2017-2019 drop-in; 2015-2016 needs pedestal kit; 2011-2014 and Cab & Chassis need Retro Fit Kit)

For a 2015-2019 6.7L Powerstroke street or light-use build with solid fueling, the KC Whistler Stage 2 is the correct drop-in performance turbo.

Frequently Asked Questions