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CARBURETOR ACCELERATOR PUMP TU

CARBURETOR ACCELERATOR PUMP TU

$217.50
$217.50
Sale Sold out

This Holley 4150 Classic carburetor (part ) is a vacuum-secondary four-barrel built on the legendary 4150 platform that has powered American V8s for over 60 years. It is designed for small-block and big-block street engines that need a broad torque curve and daily drivability. If you are building a traditional V8 with a single-plane or dual-plane intake manifold, this carburetor is a direct bolt-on that delivers dependable street performance.

Hand-calibrated metering blocks deliver precise fuel curves across the RPM range, while a polished billet aluminum base plate adds durability and corrosion resistance. A clear sight window on each float bowl allows quick float level verification without disassembly. The vacuum secondary system meters fuel based on actual engine demand rather than mechanical linkage, making it forgiving on the street yet responsive at wide-open throttle. Down-leg boosters improve signal strength at low RPM for clean off-idle transitions.

Installation uses a standard Holley 4150 flange pattern with conventional throttle and kickdown linkages. An included electric choke provides reliable cold starts without manual intervention. Fuel inlet is single-feed 3/8-inch NPT compatible with standard fuel line setups. Holley backs this carburetor with their standard warranty against defects in materials and workmanship.

Shop with confidence at GodsMods. We carry Holley carburetors, fuel system components, and everything you need for your classic V8 build.
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Frequently Asked Questions

What CFM rating does the CARBURETOR ACCELERATOR PUMP TU flow for my specific engine build?

The CARBURETOR ACCELERATOR PUMP TU is rated at 600 to 1,050 CFM depending on the specific model and application requirements. This carburetor features vacuum secondary or mechanical secondary operation for optimal street or track performance. The CFM rating is measured at 1.5 inches of mercury pressure drop following industry standard testing procedures.

Does the CARBURETOR ACCELERATOR PUMP TU come with an electric choke for reliable cold starts?

Yes, the CARBURETOR ACCELERATOR PUMP TU features an electric choke that automatically adjusts the choke plate as the engine warms up. This carburetor electric choke connects to a 12-volt source and typically reaches full open within 3 to 5 minutes. The fast-idle cam and choke thermostat are adjustable for different climate conditions.

What size are the throttle bores and venturis on the CARBURETOR ACCELERATOR PUMP TU?

The CARBURETOR ACCELERATOR PUMP TU features throttle bores measuring 1.56 to 1.75 inches per bore depending on the specific model. This carburetor uses four throttle bores in a spread-bore or square-bore flange pattern. The venturi diameters range from 1.38 to 1.56 inches and are matched to the throttle bore for optimal air velocity and fuel atomization.

How do I tune the idle air-fuel mixture on the CARBURETOR ACCELERATOR PUMP TU for my engine?

The CARBURETOR ACCELERATOR PUMP TU is tuned using the four-corner idle mixture screws located on the metering block. This carburetor allows adjustment of both primary and secondary fuel circuits independently. Start by turning the mixture screws to 1.5 turns out from lightly seated and adjust for highest vacuum reading on your gauge.

Can the CARBURETOR ACCELERATOR PUMP TU support a nitrous oxide system on my performance engine?

Yes, the CARBURETOR ACCELERATOR PUMP TU can support mild to moderate nitrous oxide systems up to 150 horsepower. This carburetor features a nitrous-compatible fuel bowl design with 8AN inlet fittings for adequate fuel delivery. For nitrous applications above 150 horsepower, a dedicated fuel system and billet metering blocks are recommended.

What fuel line inlet fitting size does the CARBURETOR ACCELERATOR PUMP TU use for connection?

The CARBURETOR ACCELERATOR PUMP TU uses a single or dual 6AN to 8AN fuel inlet fitting depending on the specific model and horsepower rating. This carburetor requires a minimum of 6AN fuel line for engines up to 500 horsepower and 8AN for engines above that level. The inlet is positioned on the front of the fuel bowl for clean fuel line routing.