Introducing our Freedom Series Cummins Performance cylinder heads. Each cylinder head is manufactured in our state-of-the-art cylinder head machine shop and guaranteed to meet or exceed factory specifications. All heads are inspected, pressure checked, decked, painted, and ready for installation. Plus, the 11 screw in freeze plugs ensure you’ll never worry about a coolant leak under the valve cover again. Whether you are sled pulling, drag racing, or just looking for extra power when towing, our Performance heads will get you the power you need and include larger Manley valves and are rated up to 1,100hp!  

• Fire ring the cylinder head (All in the head)
• 11 screw in freeze plugs (eliminates coolant leaks)
• Hardened, oversized press in valve seats
• New valve guide liners
• Manley 1.380" stainless valves
• 105 valve springs and steel retainers
• Fire ring gasket kit with multi-layer steel gasket and 4.550" diameter rings

You will be contacted about your shipping arrangements.

Core credit returns will be accepted within 180 days of original purchase. After 180 day core credit refunds will be at the discretion of SDS. Core returns after 120 days will be issued SDS store credit only.

To return your product core for credit, fill out the Return Form. SDS will email you with an RMA number and detailed return instructions. Please wait for shipment instructions before shipping any cores, many cores will be sent directly to the manufacturer.

SDS recommends using a carrier that provides package tracking to ensure your product gets back safely and quickly. You will not be reimbursed for shipping costs incurred in shipping the core. The credit card used for the purchase of the product giving rise to the core return will be credited with the core's original invoiced value after inspection.

Please drain all fluids, if any, from the core. The core returned must be a like-for-like make, model, type and part number. Cores will not be accepted from a salvage or junkyard. Cores that have been disassembled or have missing and/or damaged major components will not receive full core credit.