Generic BR-67255 650 CFM 4-Barrel Carburetor 4150 Square Bore Flange — Mechanical Secondary, Electric Choke

This Generic BR-67255 carburetor is built to replace Holley-style 4150 flange units and deliver street-friendly drivability with a 650 cubic feet per minute rating. It combines a die-cast aluminum body, dual inlet fuel bowls with sight glasses, and tuned jetting to suit V8 street engines that ask for easy throttle response and dependable starting in cooler conditions. The unit’s mechanical secondary design provides predictable power delivery while the electric choke simplifies cold-weather behavior.

How does this carburetor affect everyday driving and throttle response?

The mechanical secondary design gives linear, predictable power as the secondaries open in proportion to throttle movement, which helps avoid sudden surges. The 1-11/16" primary bore and tuned primary/secondary jets balance low-end torque with high-rpm airflow for street performance.

• 650 CFM rating supports common small-block to mid-size big-block street engines
• Mechanical secondaries ensure consistent, controllable power delivery
• Primary #70 and secondary #74 main jets provide a balanced air/fuel mix
• Electric choke aids smoother cold starts without manual choke adjustments

What are the key specifications and compatibility details?

Designed with a 4150 square bore flange, this carburetor replaces BR-67255 and fits applications that accept standard 4-bolt 4150-pattern manifolds. The 4-barrel layout and 650 CFM rating make it suitable for many street builds where drivability and moderate power are priorities.

• 4150 square bore flange — fits common Holley-style manifolds
• 4-barrel, 650 CFM airflow capacity for street and light performance use
• Primary bore: 1-11/16" for strong part-throttle response
• Includes electric choke and dual inlet fuel bowls with sight windows

How easy is installation and routine maintenance?

The BR-67255 is designed for straightforward swap-in replacement on compatible manifolds; many bolt-on installations require only fuel line, throttle linkage, choke wiring, and a quick base gasket change. The visible sight glass fuel bowls and accessible jets simplify tuning and periodic checks.

• Direct-fit 4150 flange reduces manifold modification needs
• Dual sight glass fuel bowls speed float level inspection and adjustment
• Accessible jets and removable bowls for basic carb tuning and service
• Lightweight die-cast aluminum resists heat and reduces overall weight

What performance or long-term benefits does this carburetor provide?

With corrosion-resistant die-cast construction and straightforward mechanical systems, the carburetor balances reliable seasons of use with ease of service. The combination of electric choke and mechanical secondary gives quicker, more dependable starts and a responsive driving feel across normal street conditions.

• Durable aluminum body for heat resistance and lower weight
• Electric choke improves start reliability in cool weather
• Mechanical secondaries lower the chance of bogging or abrupt throttle surges
• Visible fuel sight glasses cut inspection time during maintenance

Who is this for: The BR-67255 650 CFM 4150 carburetor is aimed at street-driven V8 owners and DIY enthusiasts upgrading or replacing Holley-style 4-barrel units. It suits builders who want a user-serviceable, moderately flowing carburetor with electric choke convenience and mechanical secondaries for controlled power delivery; ideal for small- to mid-displacement engines seeking dependable everyday performance without complex electronic controls.