Holley LT1 Hi-Ram Intake Manifold (105mm No Fuel Rails)

PN - HLY300-142

The Holley EFI Hi-Ram Intake Manifold is built to maximize performance on the GM Gen V 6.2L LT1 direct-injected engine, delivering strong airflow and high-RPM power. Its modular design makes it easy to disassemble for custom porting, top swaps, or custom induction setups. Each runner features a smooth, large-radius entry into the plenum with optimized taper and cross-sectional area for excellent performance across a wide range of engine combinations. Optional injector bosses allow you to add supplemental port injection alongside the factory direct injection for increased power potential.

Key Features & Specs

• Port size: 2.06” H x 1.53” W

• Designed for 3500–8000+ RPM power band

• Plenum volume: 549 cubic inches (with 95mm or 105mm top)

• Runner length: ~6.5”

• O-ring seals at cylinder heads and plenum top for a leak-free fit

• Rear plenum machined for MAP sensor + 3 vacuum ports

• Head flange clearance for fuel supply to the high-pressure pump

• Removable top modular design for easy changes and upgrades

• Multiple top options: 95mm, 105mm, dual 4150, dual 4500, or blank flange for custom throttle bodies

• Overall height: 13.34” (with EFI 95mm/105mm top)

• Height at plenum flange: 9.44”

• A-B height: 12.10” (with 4150/4500 carb-style top)

• Increased runner wall thickness for custom porting at runner/plenum entry

Injector Port Models (If Equipped)

• Includes fuel rails with dual injector mounting options: 1.48” or 2.56” injector length (O-ring to O-ring)

• Fuel rails are anodized, laser-etched, and machined for 8AN O-ring fittings on both ends