Cylinder Heads

Is your original cylinder head cracked or worn at the valve seats, or does your engine need better airflow? Here you'll find cylinder heads for small block and big block V8, Cummins and Duramax diesel, motorcycle engines and UTVs, available as new and remanufactured units as well as complete cylinder head kits.

What the cylinder head means for the engine

The cylinder head houses the valves, combustion chamber and intake and exhaust ports. That's why it has a major influence on how well the engine fills and empties the cylinders. A different cylinder head can change both compression and the power curve, but the result depends on the camshaft, intake, exhaust and engine management. The category includes, for example, Edelbrock cylinder heads for small block Ford, SBC and big block Chrysler, a remanufactured Cummins cylinder head from Fleece Performance for Dodge 2500/3500 6.7L, and cylinder head kits from S&S Cycle for Touring models. Ford Racing and Industrial Injection are also among the brands.

How to choose a cylinder head

• Combustion chamber: chamber volume, e.g. 72 cc, affects the compression ratio together with the piston and gasket.
• Port size: larger intake ports, e.g. 205 cc, can deliver more power at high rpm but may cost low-end torque. Choose according to displacement and rpm range.
• Valvetrain: check whether springs, retainers and rocker arms are included, and whether they suit your cam's lift.
• Fitment: check engine block, cylinder side, injector bore and whether the item is sold with or without a core exchange.

Installation and fastening

Flatness, the correct gasket and tightening torque are crucial for the cylinder head to seal. With high boost pressure or high compression, cylinder head stud kits are often chosen, as they can provide more even clamping force, while cylinder head bolt kits cover standard installation. Follow the manufacturer's tightening sequence and check valve lash after break-in where relevant.

Frequently asked questions

What does with or without core exchange mean?

With core exchange, you send in your old cylinder head as a core, e.g. when buying a CNC-machined cylinder head for Polaris XP1000/XPT. Without a core, you keep your own. Requirements for the core's condition are stated on the specific product.

Should the cylinder head be resurfaced or pressure tested before installation?

A new or remanufactured cylinder head is typically ready to install, but check the product description. If you reuse a used cylinder head, it should be pressure tested for cracks and measured for flatness, especially after overheating.

Can a different cylinder head affect inspection and approval?

It depends on the product and the vehicle. If the cylinder head changes power output or exhaust emissions, it may require documentation or re-inspection. Check the requirements and any approval for the specific part number and your vehicle before installing.