Carburetors & Accessories

Does your engine run rich at idle, or does it stumble when you floor the throttle? In this category we bring together carburetors and the parts that keep them running: rebuild kits, jets, throttle linkages, spacers and float bowls – for you who want to fine-tune, rebuild or replace the entire carburetor.

What does the carburetor and the parts around it do?

The carburetor mixes air and fuel according to how much air the engine draws in. The jets determine how much fuel is metered, and with new carburetor jets you can typically adjust the mixture when the intake, exhaust or camshaft has been changed. A spacer between the carburetor and the intake manifold can affect airflow and, depending on the material, reduce heat from the engine. The throttle linkage controls how the throttle plates open, and the float bowl keeps the fuel level stable.

How to choose the right carburetor

Flow is stated in CFM, and in this category you will find, for example, Edelbrock carburetors from 500 to 800 CFM. The right size depends on displacement, rev range, camshaft and intake – a carburetor that is too large can give poorer throttle response at low revs. When you compare carburetors, also look at:

• Choke: manual with a cable, or electric that opens automatically.
• EGR: non-EGR models have no connection for exhaust gas recirculation.
• Calibration: calibration kits can change the mixture without replacing the carburetor.
• Connections: the flange, throttle cable and fuel inlet must match your manifold and your fuel system.

Rebuilding and maintenance

Worn gaskets, a leaking needle valve or clogged passages can cause a rough idle, fuel smell or hard starting. A rebuild kit with new gaskets and wear parts can often get a used carburetor back in shape. Carburetors typically run at a lower fuel pressure than fuel injection, so check that the pump is suitable – see fuel pumps and pressure regulators. In this category you will also find brands such as QuadBoss, S&S Cycle, Moroso and Vertex Pistons.

Frequently asked questions

What is the difference between a manual and an electric choke?

A manual choke is operated with a cable from the driver's seat, so you control it yourself during a cold start. An electric choke opens gradually by itself when it receives power and warms up, and therefore requires a power supply.

When should I change the jets in the carburetor?

Typically when the intake, exhaust, camshaft or manifold has been changed so the engine gets more or less air. The spark plugs and ideally a wideband lambda reading can show whether the mixture is too rich or too lean. Change in small steps.

What does non-EGR mean on a carburetor?

It means the carburetor has no connection for exhaust gas recirculation. If your engine has an EGR system that needs to be retained, you should choose a model with an EGR connection and check the specifications for the specific part number.

Can I replace the carburetor on a registered car?

It depends on the car and the product. A different carburetor can affect the exhaust emissions and therefore the roadworthiness inspection, so check the requirements for your particular car and the documentation for the specific part number before you fit it.