Weber Carburetor Jets and Jetting Kits

In the past couple of years the quality of our fuel has changed drastically in different regions of the United States. It changes from summer to winter and seems to be different in Los Angeles or Maine compared to Texas or Alaska. To keep up with the Government mandated leaner, oxygenated fuel, Redline / Weber has had to increase the size of the idle jets in our kits 3 times due to the leaner fuel.

A properly jetted carburetor, that worked well a couple of years ago, may have lost some of its performance due to today's leaner fuels. Some symptom's of a lean fuel condition are: needing to adjust the idle too high, rough idle, hesitation or a stumble on acceleration, a flat spot at around 2500 RPM and/or surging at a constant RPM in higher gears.

Along with leaner fuels, any modifications to an engine to improve performance can compound the lean effect and require more mixed fuel volume. Modifications could be as simple as: an opened or larger air filter, an open exhaust system, or ignition modifications. Some modifications could be as extensive as a larger camshaft, head modifications, headers, or increased engine displacement. Also, altitude & extreme temperature or humidity affects the air to fuel ratio. Any and all of these modifications are exaggerated when combined with the lean fuel.

REDLINE / WEBER recognizes your need to have a variety of jets for all circuits available when tuning your engine. Our jet kits come with simple tuning instructions and a variety of jets to cover the stock and modified engine. We have designed these jet kits from years of experience jetting carburetors on engines all over the country with all types of modifications. If you are experiencing any of these symptoms from your Weber carburetor or simply want to improve the quality and performance from your engine, one of these kits is for you.