Upgrade your 2020-2025 Duramax L5P with the Wehrli Stage 3 High Flow Bundle Kit, designed for optimal performance and durability. This comprehensive kit includes OEM replacement components and high-quality aftermarket parts engineered to improve airflow, boost pressure handling, and enhance thermal efficiency. The resonator and middle boot joint feature reinforced silicone boots and stainless steel T-bolt clamps to withstand higher boost pressures and prevent leaks, ensuring reliable operation under demanding conditions. The 3.5-inch passenger side pipe boasts a CNC machined flange with a double O-ring seal and upgraded silicone boot, providing a secure fit that eliminates factory boost leaks and increases horsepower. The full assembly is finished in your choice of Wehrli’s signature custom powder coat colors, adding a personalized aesthetic touch to your truck.
The exhaust side includes a 3.5-inch down pipe, replacing the restrictive factory component for improved exhaust flow. It is black ceramic coated and heat-wrapped for superior thermal management. This down pipe connects seamlessly to the Diesel Oxidation Catalyst (DOC) outlet flange and mates with the OEM exhaust system front pipe via a four-bolt flange connection, complete with sensor bungs for easy installation. The kit also features a 4-inch aluminum intake pipe with an airbox enclosure, dry filter assembly, Outerwears pre-filter cover, and a 4-inch intake horn with a PCV port and surge ring, providing improved airflow to the engine.
Designed for easy bolt-on installation, the Wehrli Stage 3 kit retains all factory connection points and sensors, requiring no tuning for optimal performance. Made in the USA, this kit combines high-quality materials like silicone boots, stainless steel clamps, and CNC-machined flanges to ensure durability and long-lasting performance. The entire assembly is shipped in two boxes, ready to enhance your truck’s power, efficiency, and reliability with a sleek, custom finish that complements your vehicle’s look.
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