Carburettors

Carburettors — Performance Four-Barrel and Speciality Carburettor Range

The carburettor remains one of the most characterful and capable fuel delivery systems available for American performance engines. Despite the dominance of fuel injection in modern vehicles, the carburettor has unique advantages that continue to make it the preferred choice for many hot rodders, drag racers, and classic car restorers: mechanical simplicity, tuneability without a laptop, proven performance, and the kind of throttle response that can feel more immediate and connected than many EFI systems in purely carburetted applications.

With 188 carburettor products from leading names including Holley, Quick Fuel, Brawler, and Demon, our carburettor range covers everything from street-friendly 600 CFM street performers to purpose-built race units pushing well beyond 1,000 CFM.

Choosing the Right CFM for Your Engine

Carburettor sizing is one of the most frequently misunderstood aspects of carburetted engine performance. The instinct is often to fit the largest carburettor available — but an oversized carburettor on a street engine produces poor throttle response, lean transition circuits, and a fuel economy and drivability penalty that a correctly sized unit wouldn't cause. The correct approach is to match carburettor CFM to your engine's actual requirements based on displacement, maximum RPM, and volumetric efficiency.

A general starting point for a naturally aspirated street engine is to divide engine cubic inches by the peak RPM you'll actually use in normal driving, then multiply by a volumetric efficiency factor appropriate to your cylinder head and camshaft combination. Our team can assist with correct carburettor sizing recommendations for your specific application.

Double Pumper and Vacuum Secondary Designs

Double pumper carburettors — with accelerator pumps on both primary and secondary circuits — are designed for high-performance applications where instant secondary circuit opening and fuel delivery under hard acceleration is required. They're the natural choice for drag racing and aggressive performance street use. Vacuum secondary carburettors open the secondary barrels in proportion to engine demand, making them better suited to street driving where fuel economy and smooth progression matter alongside performance.

Carburettor Spacers and Adapter Plates

Carburettor spacers sit between the carburettor and intake manifold to modify plenum volume and intake velocity characteristics. Open spacers increase plenum volume, favouring top-end power. Four-hole spacers maintain velocity characteristics while increasing carburettor-to-manifold clearance for heat isolation. Adapter plates allow the fitment of carburettors with non-standard bolt patterns to standard intake manifolds, or facilitate the use of specific carburettor designs on intake manifolds designed for different configurations.