How do I identify a Holley double pumper?

It’s like a “VIN” for your carburetor and should be hand-stamped on the front of the choke tower to the right of the vent tube on most typical Holley carbs. The list number typically is four to six digits long and may or may not have a suffix number behind it. The date code will be right below it.

How do you tell if a carb is a double pumper?

The others have really covered this well, but if you have a double pumper you can tell easily with the motor off by just opening the throttle wide. You will see the gas squirt into the secondaries just like the primaries.

What year is my Holley carburetor?

See all 7 photos The list number (part number) is stamped on the air horn’s throttle-lever side (A). Below is the date of manufacture code (B). The first three numbers indicate the day of the year; the last digit, the year of manufacture.

What is a Holley double pumper?

As succinctly as possible, the double pumper is a Holley carburetor with 4 barrels, two accelerator pumps (hence the double pumper monicker), and a mechanical linkage connecting the primary and secondary sides of the carb.

Why use a double pumper carb?

The reason double pumpers (mechanical secondary carburetors is their proper name) have these twin accelerator pumps is to prevent a momentary lean situation during quick throttle blade movement. All carburetors use an accelerator pump circuit, however many only have one on the primary barrels.

What is a Holley 650 double pumper?

The Double Pumper is available in a gold dichromate or tumble polished shiny finish and features dual accelerator pumps for additional fuel under initial acceleration; mechanical secondaries for great performance; dual feed fuel inlets for constant high volume fuel delivery and a manual choke for easy control of engine …

What is the purpose of a double pumper carburetor?

Is the Holley Street Avenger a double pumper?

Bowling Green, KY – Holley Performance Products is proud to announce the introduction of their all new Ultra Street Avenger™ and Ultra Double Pumper® carburetors designed for improved performance, weight savings and show quality looks.