Engine Cylinder Head Volume Measurement Kit

What Is an Engine Cylinder Head Volume Measurement Kit?

An engine cylinder head volume measurement kit — commonly called a CC kit or head CC kit — is a precision engine-building tool used to measure the volume of a cylinder head's combustion chambers in cubic centimeters (cc). When planning an engine build, one of the most important specifications is the volume of your cylinder head's combustion chambers. After bore and stroke, combustion chamber size is the next largest factor in your engine's compression ratio. Getting this measurement right is not optional for serious engine builders — it's foundational.

Why Combustion Chamber Volume Matters

The volume of a cylinder head's combustion chamber is an incredibly important spec. Too big, and you are leaving compression on the table. Too small, and you might hurt the engine. Whether you're building a street performance motor, a dedicated race engine, or simply refreshing a high-mileage powerplant, a cylinder head CC kit is essential because it helps measure the combustion chamber volume of an internal combustion engine — a measurement that is critical for determining the engine's compression ratio, a crucial factor in engine performance.

Besides just housing your intake and exhaust valves, the combustion chamber shape and size can really increase the efficiency of your engine. With all the development in the shape of the combustion chamber, they have become a highly irregular shape, which makes them incredibly difficult to measure through traditional means. That's exactly where a dedicated CC kit comes in — it uses the principle of fluid displacement to accurately quantify an irregular volume that no ruler or caliper could capture.

What's Included in a Cylinder Head CC Kit?

While kit contents can vary by manufacturer and tier, a well-equipped CC kit typically contains the core components you need for reliable measurement. The kit includes everything necessary to take accurate readings: a burette, petcock, clamp, sturdy stand, and an acrylic base plate. The petcock is a ground-glass valve which allows for precise control of the fluid — from wide open to rapidly fill large chambers, to slow drops — allowing you to accurately get those final tenths of a milliliter into the chamber for an accurate measurement. The transparent acrylic sealing plate is equally important, as it lets the builder see directly into the chamber to confirm the cavity is fully filled and free of air bubbles before taking a final reading.

How the Measurement Process Works

The technique is straightforward but demands care. If you machine or port and polish your cylinder heads, you need to measure them. The combustion chamber volumes should all be equal, the intake runners need to match each other, and the same goes for the exhaust runners — this ensures consistent performance between cylinders. The head is laid flat, valves and spark plugs installed, the acrylic plate sealed to the deck surface, and fluid is carefully dispensed from the burette into the chamber through a small fill hole. The difference in burette volume before and after filling gives you the precise combustion chamber volume.

Choosing the Right CC Kit

CC kits come in economy and professional grades. Economy kits typically use a flask measured in 1cc increments and suit occasional users or hobbyists, while pro-grade kits feature finer graduations — with measurements on the burette marked in 0.2cc increments to ensure complete accuracy. For race engine builders or machinists who CC heads regularly, the investment in a professional-grade kit pays dividends in confidence and repeatable precision.

Top Brands in Engine Cylinder Head Volume Measurement Kits

COMP Cams is the dominant name in this category. COMP Cams Cylinder Head CC Kits accurately measure combustion chamber volumes, and their lineup spans both economy and professional configurations. Their Pro Head CC Kit is complete with a precision glass burette, stand and clamp assembly, instructions, and a plexiglass plate, and can handle up to 100cc of volume. COMP Cams is committed to providing performance-driven products that are reliable, powerful, and efficient, using the same testing methods as professional race teams to ensure their components can be trusted under any conditions.