GM LS1 Cathedral Port Hi Rise EFI Modular Intake Manifold

GM LS Cathedral Port Hi Rise EFI Modular Intake Manifold in a Natural Cast finish delivers a highly adaptable, torque-friendly platform for GM LS engines. The hi-rise design and long runners are engineered to maximize high-rpm horsepower on big-cube builds, with a modular construction that lets you tailor the setup to your application. Note: bonnet clearance may need to be checked for fitment.

Key features

• Modular design: bottom base bolts to cylinder heads and top plate bolts to the base with an O-ring seal, enabling easy customization and servicing.
• Head compatibility: accepts either cathedral port or rectangle port cylinder heads, providing flexible installation options.
• Throttle body compatibility: top plate features a short snout to accept a 102mm four-bolt GM LS throttle body; engine setup can be configured for either 102mm or 105mm throttle bodies.
• Hi-rise, long runners: designed for high rpm horsepower on large-displacement engines, ideal for drag racing and high-performance street builds.
• Port dimensions: intake port size 1.15" x 2.50" for efficient air distribution.
• Map sensor and NPT ports: rear LS-style map sensor provision plus one 3/8" NPT port and one 1/8" NPT port with bungs.
• Burst relief: burst panel welded into the top plate to vent pressure (up to 200 psi) in the event of a backfire, protecting the manifold.
• Finish options: available in natural cast (this listing) and also in black powder coat finishes.
• Injector and fuel rail compatibility: supports 14mm injector sizing with options for short length (33mm) or full length (60.6mm) injectors; EFI version includes 16 injector bosses with fuel rails and crossover, while NON-EFI versions are available without injector bosses.
• Fuel rail kit included: AF6999-6005, along with necessary hardware and gaskets for a complete installation.

What’s included

• Fuel Rail Kit (AF6999-6005)
• Intake Manifold O-Ring Gaskets (8)
• M6 x 1.00mm Hex Screws (45mm UHL) (8)
• M6 Flat Washers (8)
• 3/8" NPT Steel Port Plug (1)
• 1/8" NPT Steel Port Plug (1)
• O-Ring Gasket (AF6999-1000)

Specifications and fitment

• Overall height from front snout: 300mm (bonnet clearance should be checked)
• Port size: 1.15" x 2.50"
• 4-bolt GM LS throttle body pattern on snout
• Intake manifold accepts 14mm injectors (short length 33mm or full length 60.6mm)
• Rear LS-style map sensor provision
• Includes 3/8" NPT port and 1/8" NPT port with bungs
• Top plate with burst panel for backfire relief (up to 200 psi)

The Aeroflow Performance GM LS modular intake manifolds are designed to let you tailor the configuration to your specific application, combining a robust cast aluminium construction with a value-forward approach for the popular GM LS engine family. This hi-rise variant may require bonnet modifications for proper fitment, and the modular design ensures you can assemble the manifold to suit either EFI or NON-EFI setups while choosing injector boss counts and fuel rails as needed.