GM LS3 L98 Rectangle Port Low Rise EFI Modular Intake Manifold Black

GM LS3 L98 Rectangle Port Low Rise EFI Modular Intake Manifold - Black

Engineered for serious performance from the GM LS family, this rectangle port, low‑rise modular intake manifold blends precision casting with practical streetability. Finished in a durable black coating, it’s designed to maximize air delivery while fitting under most stock bonnets. It’s ideal for combinations using 102mm/105mm throttle bodies and 14mm short injectors, delivering a balance of high‑RPM capability and responsive throttle feel for street or strip use.

Why choose this modular design?

• Modular construction: bottom base bolts to the cylinder heads and top plate seals with an O‑ring, allowing easy disassembly and customization for different applications.
• Universal compatibility: bases fit either cathedral port or rectangle port heads, with 16 injector bosses (8 undrilled) to accommodate EFI configurations and 14mm short injectors.
• Throttle body versatility: top plate features a short snout that accepts a 102mm 4‑bolt GM LS throttle body, enabling straightforward upgrades to larger throttle bodies as your build evolves.
• Race‑proved airflow: short runners with a tapered top increase air velocity and promote even airflow distribution across all eight cylinders for improved throttle response and power delivery.

Key features and specifications

• Finish: Black powder coated (also available in natural cast in the broader lineup)
• Intake port type: Rectangle port compatible
• Port size: 1.15" x 2.50"
• Overall height (front snout): 225mm (check bonnet clearance)
• GM LS throttle body pattern on snout: 4‑bolt
• Gasket/ports: Intake manifold gasket O‑Ring (AF6999-1000); 3/8" NPT port (x1); 1/8" NPT port (x1); rear LS style map sensor provision
• Compatibility: suited for 102mm/105mm throttle body and 14mm short injectors (33mm length)
• Fuel rails and cross over: designed to be EFI with 16 injector bosses (8 undrilled), complete with fuel rails and cross over

Included components

• Fuel Rail Kit (AF6999-6003)
• 8 x Intake Manifold O‑Ring Gaskets (AF6233-5002)
• 8 x M6 x 1.00mm hex screws (45mm UHL)
• 8 x M6 flat washers
• 1 x 3/8" NPT steel port plug
• 1 x 1/8" NPT steel port plug

Performance and reliability

The Aeroflow Performance GM LS modular intake manifold delivers a robust, lightweight aluminum design that supports high rpm and big‑cubic‑inch builds. The low‑rise geometry helps you fit under a stock hood, making it an ideal choice for street cars that still demand race‑level breathing. A welded burst panel on the top plate provides a 200 psi pressure relief in the event of a backfire, protecting the manifold and downstream components.

Applications and fitment notes

• Designed to suit GM LS engines with rectangle port heads; base plates accommodate cathedral or rectangle ports.
• Bottom base anchors to the cylinder heads, top plate assembly encloses the runners with a sealed O‑ring interface for reliable sealing.
• Bonnet clearance is a key consideration; verify 225mm height from the front snout before installation to ensure compatibility with your vehicle’s hood line.