Holley 300-261 Single Plane Intake Manifold- Chevy Small Block V8 Intake Manifold 1957-1986 262ci-400ci, 1987-later with Aluminum

The 300-261 intake manifolds are designed for square-bore carburetor applications on 1957-86 262-400cid Small Block Chevrolet engines and SBC engines equipped with 1987-91 L98 aluminum Corvette cylinder heads (non-EGR applications). Also, these manifolds will work with any SBC engine equipped with aftermarket cylinder heads, as long as they have a standard port flange opening and mounting bolt locations.

The new single plane intake manifold is designed to provide a broad RPM powerband for high-performance street/strip engine applications to a maximum engine speed of 7500 RPM. The carburetor-mounting pad is designed to accept all stock or aftermarket square-bore carburetors with manual or electric chokes.

These intake manifolds are designed to accept most stock hardware and accessory brackets, but offer performance features, like an updated plenum divider area, a 1 inch shorter height than the 300-25 manifold, and a choice of two distributor clamp locations. The isolated design of the air/fuel passages helps to increase charge air density and performance.

Features and Benefits:

• Power band: 2500-7500 RPM Square Bore Carburetor Mounting Flange Isolated Water cross-over Port Size: 1.92 inch height 1.20 inch width Height: Front 4.18 inch, Rear 5.28 inch Single Plane with Isolated Plenum

Associated Comments:

• Modification to the valve covers may be required when this manifold is used with some types of cylinder heads.

Details:

• Barrel Quantity: 4.0
• Basic Operating RPM Range: 2500-7500 RPM
• Cnc Ported: No
• Carburetor Flange: 4150 Square Bore
• Carburetor Quantity: 1.0
• Carburetor Studs Included: No
• Color: Natural
• Construction: Cast
• Cylinder Head Port Shape: Rectangle
• Deck Height: 9.025 Inch
• EGR Port: No
• Engine: Chevrolet Small Block - 87+ Aluminum Heads
• Flange Style: 4150 Square Bore
• Front Maximum Height: 4.18 Inch
• Fuel Injectors Included: No
• Fuel Rail(s) Included: No
• Fuel System Type: Carb
• Gasket Or Seal Included: No
• Grade Type: Performance
• Intake Port Gasket(s) Included: No
• Manifold Type: High Rise
• Material: Aluminum
• Nitrous Bung(s) Included: No
• Plenum Finish: Natural
• Rear Maximum Height: 5.28 Inch
• Removable Runners: No
• Removable Top/Lid: No
• Single Or Dual Plane Type: Single Plane
• Throttle Body Bore Diameter: 3.6
• Throttle Body Gasket Included: No
• Throttle Body Included: No
• Vacuum Ports: Yes
• Warranty: Manufacturer's Limited 90 Day Warranty

Installation Guide: Download PDF

Installation / Product Video: Watch on YouTube

⚠️ California Proposition 65 Warning
California Residents: This product can expose you to chemicals which are known to the State of California to cause cancer or other reproductive harm. Please visit www.p65warnings.ca.gov for more information.