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Clear The Way For A Bigger Y-Bridge Without Fighting Factory Plumbing
Upgrading to a larger Y-bridge on your LB7 is a great power move until you realize the factory fuel pressure relief valve sits right where your new intake needs clearance. The WCF100023 kit from Wehrli Custom Fabrication removes that valve and blocks it off cleanly, giving your larger Y-bridge the room it needs while keeping your fuel system sealed and functional on the return side.
Key Features
- Removes the factory fuel pressure relief valve for Y-bridge clearance
- Stainless steel block off plug resists corrosion under the hood
- Includes 5/16 inch fuel line and brass tee fitting for a clean return route
- Hose clamps included for a secure, leak free connection
- Simple bolt-on kit installs with basic hand tools
- Part number WCF100023 designed specifically for the LB7 intake runner
Vehicle Fitment
| Year Range | Make | Model |
|---|---|---|
| 2001-2004 | Chevrolet | Silverado 2500HD |
| 2001-2004 | Chevrolet | Silverado 3500 |
| 2001-2004 | GMC | Sierra 2500HD |
| 2001-2004 | GMC | Sierra 3500 |
Fits any 2001-2004 truck equipped with the 6.6L LB7 Duramax diesel engine.
Specifications
| Detail | Value |
|---|---|
| Manufacturer Part Number | WCF100023 |
| Brand | Wehrli Custom Fabrication |
| Block Off Plug Material | Stainless Steel |
| Fuel Line Size | 5/16 Inch |
| Fitting Type | Brass Tee Fitting |
| Engine Application | 6.6L LB7 Duramax |
| Condition | New |
What's Included
- 1x Stainless Steel Block Off Plug
- 1x 5/16 Inch Fuel Line
- 1x 5/16 Inch Brass Tee Fitting
- Hose Clamps
About Wehrli Custom Fabrication
Wehrli Custom Fabrication, known as WCFab, has been building precision diesel performance parts for Duramax, Power Stroke, and Cummins platforms for years. Their fuel system components and Y-bridge clearance kits are designed to solve the real fitment problems diesel owners run into when upgrading intake and turbo hardware.
Frequently Asked Questions
What is the WCF100023?The WCF100023 is a fuel pressure relief valve delete kit from Wehrli Custom Fabrication that removes the factory relief valve on the LB7 intake runner to provide clearance for larger aftermarket Y-bridges.
Do I need this kit if I am not installing a larger Y-bridge?No, this kit is specifically intended for owners upgrading to a larger Y-bridge that would otherwise contact the factory relief valve. If you are running the stock Y-bridge, you likely do not need this kit.
Will removing the relief valve affect my fuel system pressure?This kit blocks off the relief valve port and reroutes the return line through the included fittings, so your fuel system continues to operate normally without the relief valve in place.
Does this kit require welding or cutting?No, this is a bolt-on kit that uses the factory mounting location and included hose clamps and fittings for a clean installation.
Can I install this kit myself at home?Yes, this is a straightforward install with basic hand tools. Most owners complete it in under an hour.
Will this work with any aftermarket Y-bridge?The WCF100023 clears clearance issues for most larger aftermarket Y-bridges, but always check your specific Y-bridge manufacturer's fitment notes since bridge designs vary.
Does this kit come with a warranty?Wehrli Custom Fabrication backs this kit against manufacturing defects. Reach out to us with your order details if you run into any issues.
Can I return this if I no longer need it?Yes, unused kits in original condition can be returned within our standard return window. Contact our support team to start the process.
Is a fuel system bleed needed after installation?Yes, it is good practice to check for leaks and prime the fuel system after installation before driving.
Install Instructions
- Relieve fuel system pressure before beginning work
- Locate the factory fuel pressure relief valve on top of the LB7 intake runner
- Remove the factory relief valve and associated fuel line
- Install the stainless steel block off plug in place of the relief valve
- Connect the included 5/16 inch fuel line and brass tee fitting to reroute the return line
- Secure all connections with the included hose clamps
- Check all fittings for tightness and inspect for leaks
- Start the engine and verify no fuel leaks are present before driving
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