This Holley Hi-Ram EFI intake manifold base is designed for 1965-and-later 396-502+ MKIV-MKVI Big Block Chevy engines with standard intake flange rectangle-port cylinder heads, bringing modern EFI induction technology to the classic BBC platform.
Specifications:
- Basic Operating RPM Range: 1500-8000
- Engine Fit: Chevy Big Block V8, 9.80 in. deck height
- Fuel System Type: EFI
- Manifold Type: Hi-Ram (Lower Manifold Base)
- Construction: Cast 356-T6 Aluminum, Natural Satin As-Cast Finish
- Vacuum Ports: Yes
- Port Flange Openings: 2.40 in. tall x 1.60 in. wide, uses Mr. Gasket intake manifold gasket #5817
- Warning: California Proposition 65
- Warranty: Manufacturer's Limited 90-Day Warranty
- Part Number: 300-961
Includes black anodized EFI fuel rails machined for -10AN O-ring fittings; requires an early-type GM or small-cap MSD/Holley distributor (not compatible with HEI). Coolant outlet uses a standard Chevy thermostat housing flange with (2) 1/2 NPT and (1) 3/8 NPT ports; MAP sensor port fits a GM Gen IV LS MAP sensor.
FAQ
What Big Block Chevy engines does this base fit?
1965-and-later 396-502+ MKIV-MKVI Big Block Chevy engines with a standard 9.80 in. deck height and rectangle-port cylinder heads.
What gasket does it use?
Mr. Gasket intake manifold gasket #5817, with 2.40 in. x 1.60 in. port flange openings.
Does it include EFI fuel rails?
Yes, black anodized EFI fuel rails machined for -10AN O-ring fittings are included.
What distributor is required?
An early-type GM or small-cap MSD/Holley distributor; not compatible with HEI distributors.
What's the operating RPM range?
1500-8000 RPM.
