GM LS3 L98 Rectangle Port Low Rise EFI Modular Intake Manifold

Aeroflow Performance GM LS Modular Intake Manifold — Low Rise Rectangle Port EFI

The GM LS Rectangle Port Low Rise EFI Modular Intake Manifold from Aeroflow Performance is a cast aluminium, modular solution designed for the GM LS engine family. Its low-rise profile fits under most stock bonnets while delivering a precise, high-flow path for 8 cylinders. The top plate’s short throttle body snout accepts a 102mm GM LS throttle body, and the design accommodates 14mm short-length injectors, providing a streamlined, high-performance intake option for street or strip use.

Key specifications include a 1.15" x 2.50" port opening, an overall height of 225mm from the front snout (bonnet clearance should be checked), and a 4-bolt GM LS throttle body pattern on the snout. The manifold offers one 3/8" NPT port and one 1/8" NPT port, plus a GM LS style MAP sensor provision on the rear. The included gasket is an intake manifold gasket O-Ring (AF6999-1000).

What’s included

• 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
• Intake Manifold gasket O-Ring (AF6999-1000)

The modular design centers on a base that bolts to the cylinder heads and a top plate that seals with an O-ring. The top plate’s short throttle body snout accepts a 102mm GM LS four-bolt throttle body, with a rear-mounted MAP sensor provision and additional ports for versatility. A burst panel welded into the top plate releases pressure (up to 200 psi) in the event of a backfire, protecting the manifold and intake system.

Performance and versatility

Short intake runners with a tapered top are engineered to increase air velocity and promote more even airflow distribution to all eight cylinders, improving throttle response and overall performance. The base is compatible with either cathedral port or rectangle port cylinder heads, and the manifold can be purchased as a complete kit or as individual components. You can choose between finishes: natural cast or black powder coat, depending on your build aesthetics.

Applications include high-rpm, big-cube setups for serious drag racing, as well as street-driven cars where bonnet clearance is a priority. For those seeking a true modular solution, Aeroflow’s GM LS manifold lets you tailor EFI vs. non-EFI configurations with injector bosses (16 total, 8 pre-drilled) and complete with fuel rails and crossover designed to suit 14mm short-length injectors.