HSP Diesel 2001-2004 LB7 Duramax Stock Turbo Inlet Horn - 103-HSP

HSP Stock Turbo Inlet Horn for 2001-2004 Chevrolet / GMC Duramax LB7

The 103-HSP, also known as the HSP Stock Turbo Inlet Horn, is designed for the 2001-2004 LB7 Duramax-equipped Chevrolet and GMC trucks. This is a highly effective upgrade over the restrictive factory component and a must-have for anyone looking to improve airflow and overall performance.

Why You Need the HSP Stock Turbo Inlet Horn

The factory turbo inlet horn on LB7 trucks is poorly designed and highly restrictive. Its small diameter and awkward bends limit airflow to the turbocharger, choking its performance. This component also offers no visual appeal or performance benefit under the hood. HSP Diesel recognized the need for improvement—and delivered.

What Makes the HSP Stock Turbo Inlet Horn Different?

HSPs version features a massive 3.5" diameter—far superior to the OEM part. The larger, smoother interior increases airflow and reduces restrictions. This allows the stock IHI turbocharger to spool faster and breathe easier, which translates into improved power and torque. Many customers report noticeable gains with just this part alone, and when paired with the HSP Cold Air Intake, it can help lower exhaust gas temperatures (EGTs).

Whats Included

• 1x Max Flow Inlet Horn (HSP-IN-235)
• 1x LB7 Turbo Inlet O-Ring (RFB-819-RFAB)
• 3x M6x1.0x20mm Button Head Screws (RFB-908-RFAB)

Fitment

• LB7: 2001-2004 (VIN Code 1)

How to identify the VIN code: The 8th character of the VIN indicates engine type, while the 10th character identifies the model year.

Special Note: Only install this part using the supplied bolts. Do NOT attempt to install with factory hardware.

Overview

• Direct replacement for factory applications
• Significantly increased airflow
• Improved horsepower and torque
• Faster turbo spool-up
• Extended turbo life
• Powder coating options available for a cleaner engine bay

Our Warranty

HSP NO BS LIMITED LIFETIME WARRANTY

At HSP, we believe in our products and stand firmly behind every one we manufacture. For years weve supported our customers with unmatched service—even without a formal policy. Now, with our No BS Lifetime Warranty, you can count on a clear process and a commitment that lives up to its name.

For more information about our Lifetime No BS Warranty, click HERE.