Intake Manifold for Pontiac GTO (2005-2006) Cathedral Port Black w/Fuel Rail EFI

High-Flow Aluminum Intake Manifold for 2005-2006 Pontiac GTO (LS2 / V2)

What it is for: Replaces the restrictive factory composite intake manifold to maximize upper-RPM airflow and accommodate throttle body EFI or carbureted setups on cathedral port cylinder heads.

The Stock GTO Composite Manifold Limitations

The OEM plastic LS2 intake manifold is notorious among engine builders for structural limitations under boost and restrictive airflow distribution at higher RPMs. The factory composite material, while adequate for stock output, suffers from significant heat soak during sustained load and lacks the structural rigidity needed for high manifold pressures. Furthermore, the internal runner design chokes volumetric efficiency beyond 6,000 RPM, choking top-end breathing and limiting the true power potential of the 6.0L powerplant.

The Engineering Solution

This single-plane aluminum intake manifold is engineered specifically for LS1, LS2, and LS6 cathedral port heads, completely eliminating the structural weaknesses of the factory plastic unit. Featuring a 4150 square bore carb base and optimized 2.50" x 1.15" port dimensions, this manifold delivers a broad, usable powerband from 2,500 to 7,000 RPM. The cast aluminum construction resists ballooning and handles extreme forced induction pressures without failure. Standing at a 5.417-inch intake height, it provides superior plenum volume for multi-port EFI configurations. The included high-flow fuel rails and complete mounting hardware ensure precise injector alignment and a reliable installation. Finished in a stealthy black coating, it resists chemical degradation in harsh engine bay environments. The direct-bolt fuel rails are machined to support high base fuel pressures, ensuring uniform delivery across all eight cylinders to prevent lean conditions during peak engine load.

Technical Specifications

Compatibility

• For GM LS1 Engines (Cathedral Port)
• For GM LS2 Engines (Cathedral Port)
• For GM LS6 Engines (Cathedral Port)

The Pontiac Muscle Caliber

Engineered to handle the rigorous demands of large-displacement, high-horsepower applications, this manifold unlocks the aggressive top-end power and throttle response expected from American muscle, providing a rock-solid foundation for both naturally aspirated track cars and high-boost forced induction builds.