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

Aeroflow Performance’s GM LS modular intake manifold in Black is engineered for the GM LS3/L98 rectangle-port setup. This cast aluminium, hi-rise design offers a scalable, configurable solution for high-rpm power while remaining a practical choice for street or race applications. The modular base and top plate seal with an O-ring, delivering a robust, leak-free platform that can be tailored to your engine and fuel system needs.

Key features

• Hi-rise design with long runners for high RPM horsepower on big‑cube LS engines; bonnet clearance will be required for the hi-rise option.
• Rectangle port compatibility with a base that fits either cathedral port or rectangle port cylinder heads.
• Top plate features a short snout to accept a 102mm four‑bolt GM LS throttle body; compatible with 102mm/105mm throttle bodies.
• Short 33mm (14mm) injector suitability—uses 14mm short-length injectors with 16 injector bosses (8 undrilled) for EFI setups.
• Overall height from the front snout is 300mm (check bonnet clearance).
• 3/8" NPT port (x1) and 1/8" NPT port (x1) on the base, plus a rear LS-style map sensor provision.
• Burst panel welded into the top plate to vent pressure (up to 200 psi) in the event of a backfire, protecting the manifold.
• Modular design: bottom base bolts to the cylinder heads and top plate bolts to the base with an O-ring seal; each base accommodates either cathedral or rectangle port heads.
• Available in natural cast or black powder coat finishes; this listing features the Black finish.

What’s included (EFI configuration)

• Fuel Rail Kit (AF6999-6004)
• 8 x Intake Manifold O-Ring Gaskets (AF6233-5002)
• 8 x M6 x 1.00mm Hex Screws (45mm UH L)
• 8 x M6 Flat Washers
• 1 x 3/8" NPT Steel Port Plug
• 1 x 1/8" NPT Steel Port Plug
• Intake manIfold gasket O‑Ring (AF6999-1000)

Technical specifications at a glance

• Port size: 1.15" x 2.50"
• Intake manifold gasket O‑Ring: AF6999-1000
• 3/8" NPT port (x1) and 1/8" NPT port (x1)
• Rear LS-style map sensor provision
• Overall height from front snout: 300mm
• Gasketed, o-ring sealed modular base/top plate

Design & performance considerations

The Aeroflow Performance GM LS modular intake manifold couples a compact bottom base with a precision-machined top plate to deliver a sealed, tunable airflow path. Short runners with a tapered top promote increased air velocity and more uniform airflow to all eight cylinders, boosting throttle response. The long-runner hi-rise option is ideal for drag racing and high‑rpm applications, while the base features ports for LS map sensing and multiple NPT ports for ancillary sensors or fixtures. A cutaway burst panel on the top plate provides a safety vent for backfires, preserving component integrity under extreme conditions.

Applications & fitment

• Designed for GM LS3/L98 rectangle-port engines with the option to run EFI or non‑EFI configurations (16 injector bosses total, 8 drilled in EFI, 8 undrilled).
• Suitable for installation with 102mm or 105mm throttle bodies and 14mm short-length injectors (approx. 33mm length).
• Bonnet clearance considerations apply due to hi-rise design; verify fitment before installation.
• Compatible with either natural cast or black powder-coated finishes; this listing reflects the Black finish.

With its modular, scalable approach, this intake manifold provides a tailored path to higher performance on GM LS engines while maintaining a practical, installable solution for both street and competition use.