Holley 300-123 EFI Hi-Ram Manifold, LS1/LS2/LS6, 105mm

The Holley GM LS1/LS2/LS6 Modular Hi-Ram Intake Manifold is introduced as a cost effective alternative to fabricated sheet-metal for high-performance applications where induction system height is not limited. Coupling this Hi-Ram intake with the high flowing LS1/LS2/LS6 style cylinder heads has outstanding potential for N/A and forced induction applications at a budget-minded cost. Aggressive, bold, race-bred styling will make bad intentions clear for drag race, muscle car, marine, off-road, sandrails, pulling trucks, track, street-rod applications and more! The base is designed to be modular in configuration to accept a wide range of carbureted and EFI tops and to be attractive to builders and fabricators as the foundation for custom induction systems. Runner length and the tapered cross-section designed to perform well for a wide range of engine configurations EFI fuel rails are machined for -8AN O-ring Fittings with passages large enough to accommodate high fuel flows and dampen pressure pulsations in the fuel system and come standard with EFI Hi-Ram kits. Cast aluminum construction. Intended for use on N/A or forced induction engines in the 6.0 to 7.0+ liter range, max power at 7000-8000+RPM.

• Base Plenum Top Mounting Flange Height - 8.42 to the lifter valley cover flange on engine block.
• Total Height with 92/105mm EFI Plenum Top - 12.32 to the lifter valley cover flange on engine block.
• Runner Length - 6.58 , As-Cast Runner Cross-Sectional Area - Tapered 4.25 in² to 2.53 in²
• Throttle Body Flange Location, with 92/102mm EFI Plenum Top : Height - 8.42 (from engine block lifter valley cover flange), Longitudinal Location - 3.84 (forward from engine block front flange), Angle - 25 deg. (down from vertical)
• Plenum Top Gasket Type - 3/32 Round O-ring Cord
• Mounting Flange Gasket Type - Standard LS3 Molded O-Ring
• Port Size - 2.49 Height x 1.21 Wide

Installation Instructions (PDF)