Rochester Quadrajet primary metering rods are used to tailor primary part throttle air/fuel enrichment . Fits most 1975 and later non-electronic Rochester Quadrajet carburetors, except some truck and marine carburetors that use the early style rods. Dimension stamped in rod indicates maximum diameter of taper.
Quantity: 2 Primary Metering Rods for Rochester Quadrajet carburetors.
Cruise diameter: .058"
Power tip diameter:.026"
Rod overall length: 2.395" - 2.400"
58P is stamped into rod shaft.
Does NOT fit Quadrajets with Electronic Mixture Control Solenoid (MCS)
Primary Rod Tech:
Rods have a large diameter and a small diameter "power tip". The larger diameter section of the rod is positioned in the metering jet during light throttle driving. During heavy acceleration, manifold vacuum decreases allowing the power piston to rise positioning the small diameter power tip in the metering jet.
Larger diameter rods will lean part throttle/cruise air fuel mixtures. A great way to fine tune your Q-Jet for better driveablity and fuel mileage.