Wehrli 17-19 6.6L Duramax L5P Stage 3 High Flow Bundle Kit - Candy Red

Combining intake, intercooler, and exhaust-side upgrades into one box, this Wehrli Stage 3 bundle in Candy Red is a comprehensive airflow overhaul for the 2017-2019 L5P Duramax. It builds on Wehrli's Stage 2 kit and adds a 3.5-inch ceramic coated down pipe, so the air path is upgraded from the filter all the way past the turbo.

On the intake side, a 4-inch aluminum intake pipe with an air box enclosure, dry filter assembly, and Outerwears hydrophobic pre-filter cover replaces the restrictive factory plastic components. The intake horn is over an inch larger in diameter than OEM and includes a PCV port and surge ring. All-aluminum 14-gauge construction with smooth mandrel bends draws cold air through the hood ram air duct and inner fender. Wehrli reports a 25 HP gain with their 4-inch turbo inlet when used with a max effort tune.

After the turbo, a 3-inch one-piece driver side intercooler pipe replaces the factory 2.5-inch two-piece resonator-equipped tube, and a 3.5-inch passenger side pipe replaces the leak-prone factory plastic and rubber piece. Both are made from 14-gauge aluminum with mandrel bends and CNC machined flanges. The passenger side features double O-ring seals and an upgraded silicone boot. On the exhaust side, the 3.5-inch down pipe replaces the restrictive crushed factory part with a ceramic coated and heat-wrapped unit that connects to the DOC outlet flange and mates with the OEM exhaust front pipe.

No tuning is required. All factory sensor connections and mounting points are retained. Silicone boots, stainless T-bolt clamps, O-rings, and hardware are included. Made in the USA.