Quick Fuel Technology 34-10 Billet Metering Block User Manual

Quick Fuel Technology 34-10 Billet Metering Block User Manual


P/N 34-10


Installation Instructions for 34-10 Billet Metering Block

Thank you for purchasing our Pro Billet two circuit gasoline metering block.

Installation is essentially the same procedure as replacing a conventional metering block. There are a couple of features and tuning aspects of this metering block you should become familiar with. At the top of the straight “V” is the idle feed restriction (see illustration below). This screw-in restriction controls the fuel side

of the idle and off-idle air/fuel mixture. Your metering block comes with .035” idle feed restrictions. The number “35” will be stamped on the head of these restrictions.

The emulsion holes, the five emulsion bleeds in the serpentine slot are pre-calibrated. These pre-calibrated emulsion bleeds are as follows from top to bottom: .028”, .028”, .030”, blank, .032”. This emulsion pattern is

a race proven combination and works for most applications where the carburetor size is correct for the engine.

An additional feature of the Pro Billet metering block is an adjustable power valve channel restriction. These are the holes immediately behind the power valve 1” hex head. The purpose of these restrictions is to add supplemental fuel to the main well during wide open throttle operation or when the engine load drops the manifold vacuum below the calibrated value of the power valve. In this metering block the power valve channel restrictions are .063” and should have the number “63” stamped on the head.

CAUTION: Do not make drastic emulsion size changes as you can significatly alter the air/fuel mixture ration and could cause damage to the engine. It is highly recommended that when experimenting with emulsion calibration you consult one of the many books available on carburetor modification and use one or more devices that montors air/fuel ratio throughout the operating RPM range.

Typical QFT 2-Circuit Billet Metering Block

Idle Feed


Emulsion Bleeds

Power Valve Channel


We thank you for purchasing Quick Fuel Technology products. We are passionate about about our products and your performance - if you are experiencing any difficulty in your installation or are having other issues please call our technical serivce phone line at 270-793-0900. Our business hours are M-F 8:00 am - 5:00 pm Central Time.