Mazworx SR20VE Stage 4 Pro Drag Cylinder Head Turbo

The Mazworx SR20VE Stage 4 Pro Drag Cylinder Head Turbo is the premium choice for high-performance Nissan SR20VE engines, specifically designed for Pro Drag applications. Built with precision and advanced machining techniques, this cylinder head is engineered to maximize airflow, durability, and reliability under extreme conditions.

Comprehensive Build Process

Each cylinder head starts with a thorough hot tank cleaning to remove oil and grime, ensuring a pristine base. Due to the age of many cores, a sand blasting process is performed to eliminate corrosion and debris, giving the head a uniform satin aluminum finish and improved appearance.

Oil port plugs and freeze plugs are meticulously removed, re-tapped, and reinstalled to enable comprehensive cleaning of all oil galleries. Freeze plugs are also replaced during this step to maintain integrity.

Performance Enhancements

• Shimless Valves: Eliminates the traditional shim setup between valves and rockers, reducing the risk of components coming loose at high RPMs and enhancing reliability.
• Stage 4 CNC Port and Polish: Developed and optimized on a Superflow 600 flow bench, this porting maximizes intake and exhaust flow, perfectly paired with the Pro Drag SR20 intake manifold for peak performance.
• 90mm CNC Combustion Chamber: Opens the combustion chamber by removing squish areas that can create hot spots and detonation under boost, improving valve breathing and overall combustion efficiency. See the process here.
• Valve Guide Service: Removal, reinstallation, and precision reaming of valve guides, replaced with premium Supertech bronze guides designed for durability and heat resistance.
• Copper Alloy Valve Seats: Superior to OEM iron seats, these are larger to support the bigger valves and withstand high boost and methanol use.
• Multi-Angle Valve Job: A five-angle plus radius valve seat finish increases airflow and sealing efficiency.
• Head Stud and Dowel Pin Machining: The cylinder head stud holes are machined to fit 1/2″ studs, with dowel pin locations designed for 16mm pins to enhance head stability.
• Surface Finishing: Resurfaced using poly-crystalline diamond (PCD) tooling to ensure a smooth, flat sealing surface.

Assembly and Setup

The head is fully assembled with precision-set valve lash to match the camshaft’s specifications. New valve seals are installed to prevent leaks and ensure longevity.

Included Components

• Mazworx 36mm Intake and 32mm Inconel Exhaust Shimless Valves
• Supertech Titanium Retainers
• Supertech Dual Valve Springs (123 lb)
• Supertech Bronze Valve Guides
• Ferrea Billet Valve Locks
• Kelford 184-X Pro Drag SR20VE VVL Killer Cams
• Viton Valve Seals
• Oil Port Pipe Plugs
• Threaded Freeze Plugs

Core Policy

If you have a cylinder head to send in, machining and assembly will commence upon receipt. For customers without a head, please contact Mazworx to arrange purchasing a core.