TMF Raw Flow Gen1 M8 Heads – Ultimate Performance Cylinder Heads for Harley-Davidson Milwaukee-Eight (Gen1) Engines
Unlock the full potential of your Harley-Davidson Milwaukee-Eight Gen1 engine with the TMF Raw Flow Gen1 M8 Heads. These premium, hand-crafted cylinder heads are meticulously built for serious performance enthusiasts seeking massive gains in horsepower, torque, and throttle response. Designed specifically for 2017-2023 air/oil-cooled Milwaukee-Eight engines, the Raw Flow Gen1 series features extensive custom modifications that dramatically improve airflow, velocity, and combustion efficiency – delivering the kind of raw power that transforms your ride.
Each set begins with your supplied cores undergoing a thorough disassembly, inspection, and cleaning process to ensure a flawless foundation. We then incorporate oversized +2mm intake valves (available in durable steel or lightweight titanium options) for superior breathing, paired with a multi-radius competition valve job that optimizes valve seating and flow at all lift points.
The heart of these heads is the extensive custom hand porting of intake and exhaust runners, combined with hand-ported combustion chamber modifications for unshrouded valves and enhanced swirl – resulting in explosive combustion and broader power delivery. Premium performance bronze intake and exhaust valve seats provide exceptional durability under high heat and stress, while new valve stem seals ensure long-term reliability.
To address common M8 design quirks, we weld the cooling passage hole for improved structural integrity and coolant flow management. The head gasket surface is re-machined for a perfect seal, eliminating leaks and ensuring maximum compression.
Built for aggressive cams, these heads include a high-lift spring kit supporting .640" lift (steel or titanium retainer options available), allowing you to run high-performance camshafts without coil bind or valve float. Finally, every set is precision assembled and tested on our flow bench to guarantee consistent, race-proven performance.
Key Benefits:
- Dramatically increased airflow and velocity for 20-30+ HP gains (depending on supporting mods like cams, exhaust, and bore kits)
- Broader torque curve for street-ripping acceleration and highway passing power
- Hand-crafted attention to detail – not just CNC, but artisan-level porting for unmatched flow characteristics
- Ideal for 114ci to 131ci+ builds, big bore kits, and high-compression setups
- Bolt-on compatibility with stock or aftermarket components
- Flow Tested Rated for 380CFM+ Average
Important: This is a Core Exchange Required product. You must ship us your good, reusable Milwaukee-Eight Gen1 cylinder head cores for modification. Cores must be in rebuildable condition (no cracks, stripped threads, or severe damage). Contact us prior to purchase for core inspection guidelines and shipping instructions.
Whether you're building a high-output street bagger, a drag-strip terror, or a torque-monster touring bike, the TMF Raw Flow Gen1 M8 Heads deliver uncompromising performance without compromise. Sold as a pair (left and right heads).
Elevate your Milwaukee-Eight to legendary status. Order your Raw Flow Gen1 M8 Heads today!
