SKU: WCF100414-GRY
Wehrli Custom Fabrication Stage 2 High Flow Bundle Kit (Grey) – 2020-2024 Duramax L5P
The Wehrli Custom Fabrication Stage 2 High Flow Bundle Kit is a comprehensive performance upgrade for 2020-2024 GM Duramax L5P 6.6L diesel engines. This grey powder-coated kit includes a 4″ turbo inlet for increased airflow (with tested gains of up to 25 HP when paired with a Max Effort tune), a high-flow air filter with removable lid and hydrophobic pre-filter cover, plus upgraded 3″ driver-side (hot) and 3.5″ passenger-side (cold) intercooler pipes. The heavy-duty 14-gauge aluminum construction with smooth mandrel bends eliminates the restrictive factory 2.5″ resonator-equipped pipes and leak-prone plastic/rubber components. The kit comes with all necessary high-quality hardware, silicone boots, seals, and stainless steel T-bolt clamps for a durable, easy installation that optimizes flow while protecting the MAF sensor, turbo, and engine airways.
Key Features
- 4″ Turbo Inlet – Increases airflow with up to 25 HP gains when used with a Max Effort tune
- High-Flow Air Filter – Removable lid for easy inspection and maintenance with included hydrophobic pre-filter cover
- 3″ Driver-Side (Hot) & 3.5″ Passenger-Side (Cold) Intercooler Pipes – Replaces restrictive factory 2.5″ pipes for improved flow and durability
- Heavy-Duty 14-Gauge Aluminum – Mandrel-bent for smooth, aerodynamic performance and long-term reliability
- Grey Powder Coat Finish – Attractive, corrosion-resistant finish with all necessary hardware included
| Spec | Detail |
|---|---|
| Part Number | WCF100414-GRY |
| Brand | Wehrli Custom Fabrication (WCFab) |
| Type | Stage 2 High Flow Bundle Kit (Grey) |
| Compatibility | 2020-2024 Duramax L5P 6.6L Diesel |
| Material | 14-Gauge Aluminum with Grey Powder Coat |
| Country of Origin | United States |
Whats Included
- 4″ Turbo Inlet
- High-Flow Air Filter with removable lid and hydrophobic pre-filter cover
- 3″ Driver-Side (Hot) Intercooler Pipe
- 3.5″ Passenger-Side (Cold) Intercooler Pipe
- High-quality hardware, silicone boots, seals, and stainless steel T-bolt clamps
- Installation instructions
Product Notes
- Designed specifically for 2020-2024 GM Duramax L5P engines
- Improves airflow and reduces restrictions for better performance and efficiency
- Grey powder coat finish provides a clean, durable appearance
Installation Notes
- Bolt-on installation with no major modifications required
- Estimated time: 2–4 hours
- Professional installation recommended for best results
This Part Fits
| Year Range | Make | Model | Engine | Notes |
|---|---|---|---|---|
| 2020-2024 | Chevrolet / GMC | Silverado 2500/3500 HD & Sierra 2500/3500 HD | 6.6L Duramax L5P | Stage 2 High Flow Bundle Kit (Grey) |
Why Choose Wehrli Custom Fabrication High Flow Kits?
- Handcrafted in the USA with heavy-duty materials for maximum durability
- Significant airflow improvements for better performance and efficiency
- Complete bundle kits with all necessary components for a professional installation
Frequently Asked Questions
- Q: Does this Stage 2 kit fit my 2022 GMC Sierra 2500HD 6.6L Duramax L5P?
A: Yes, designed for all 2020-2024 GM Duramax L5P 6.6L diesel engines in Silverado and Sierra 2500/3500 HD trucks. - Q: What kind of power gains can I expect?
A: The 4″ turbo inlet alone has shown up to 25 HP gains when paired with a Max Effort tune. - Q: Is professional installation required?
A: Recommended for best results, though the kit is designed for straightforward bolt-on installation.
Shipping & Handling
- Method: Ground UPS or FedEx
- Availability: In stock – ships same or next business day
- Packaging: Official Wehrli Custom Fabrication retail box





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