Sport Air Intake System for Cadillac Seville SLS / STS (1998-2004) with 4.6L V8 Engine Blue

Restore the Breath of Your 4.6L Northstar V8 Cadillac Seville SLS & STS

Who It’s For: Designed specifically for 1998–2004 Cadillac Seville owners running the legendary 4.6L Northstar V8 engine.

The Problem: The Northstar V8 is a high-revving, 32-valve masterpiece, but the factory air box was engineered for silence over performance. The stock plastic housing and restrictive paper filters create a significant bottleneck, preventing the engine from reaching its true volumetric efficiency. Over time, these factory plastic components can become brittle and heat-soaked, further robbing your Cadillac of its luxury-performance edge.

The Solution: We engineered this Sport Air Intake to eliminate the factory restrictions of the Northstar V8. By replacing the baffled stock air box with a high-velocity T304 aluminum tube and a high-flow washable filter, we allow the engine to pull in a higher volume of oxygen with less resistance, correcting the factory’s conservative airflow tuning.

Why This is the Ultimate Upgrade

• Optimized Air Velocity: Delivers up to a 10% increase in horsepower and torque by reducing intake turbulence and increasing the volume of air reaching the manifold.
• Professional Grade Materials: Constructed from mandrel-bent T304 lightweight aluminum piping which dissipates heat faster than stock plastic and provides a lifetime of durability.
• Deeper V8 Note: Removes the factory resonators to provide a deep, sporty engine growl under acceleration while maintaining cabin refinement during cruising.
• Long-Term Value: Features a high-performance washable filter that only requires maintenance every 50,000 miles, eliminating the need for expensive paper filter replacements.

Technical Specifications

Compatibility & OEM Reference

Fits the Following Vehicles:

• 1998 Cadillac Seville SLS / STS 4.6L V8
• 1999 Cadillac Seville SLS / STS 4.6L V8
• 2000 Cadillac Seville SLS / STS 4.6L V8
• 2001 Cadillac Seville SLS / STS 4.6L V8
• 2002 Cadillac Seville SLS / STS 4.6L V8
• 2003 Cadillac Seville SLS / STS 4.6L V8
• 2004 Cadillac Seville SLS / STS 4.6L V8

Interchange Part Numbers:

SI-C-12B, 1998, 1999, 2000, 2001, 2002, 2003, 2004, Cadillac, Seville, SLS, STS, 4.6, 4.6L, V8, Northstar

The Performance Promise

Buy with confidence. This system is designed for a direct bolt-on installation using basic hand tools in under 60 minutes. It is a legal and effective way to improve throttle response without voiding your vehicle’s warranty. After installation, we recommend disconnecting your battery for 10 minutes to allow the PCM to recalibrate for the increased airflow.