Maximise the performance of your Gen 1 MINI with our precision CNC ported big valve cylinder head – engineered specifically for the R50, R52 and R53 One, Cooper, Cooper S, JCW and GP models. Suitable for both naturally aspirated and supercharged engines, this upgrade significantly improves airflow, boosts horsepower, and enhances engine response across the rev range.

The ported head features fully CNC machined exhaust and intake ports. While the factory intake ports are serviceable, the exhaust side is highly restrictive, a known bottleneck for MINI engines. Our porting process focuses on addressing this with precision machining for smoother, higher-capacity flow, delivering excellent gains in throttle response and power output.

To maximise efficiency, this head is fitted with oversized Supertech valves – 25.5mm (2.3mm oversized) Inconel single groove valve exhaust valves and 32mm (+1.8mm oversized) nitride coated single grooved intake valves. Valve seats are accurately re-cut, and the combustion chambers are reshaped to reduce hotspots and minimise the risk of detonation, particularly under high load or boost.

The cylinder heads are assembled with Supertech beehive performance valve spring kits and retainers to deal with high revving applications and eliminate valve float.

Technical flow data for the ported big valve cylinder head is presented in the images.

No Exchange Unit Required
This cylinder head is supplied outright, with no need for your original unit to be returned. That means faster installation, less downtime, and full flexibility when planning your engine build.

Recommended Supporting Mods for Safe, Reliable Performance
To get the most from your ported big valve head and ensure safe running, we recommend the following supporting upgrades:

ECU Masters EMU Black ECU with custom tuning – for full control of fuelling and ignition maps and provides wide band lambda control to deliver live fuel trims and safe guard your investment
Lohen High Flow In-Tank Fuel Pump – to maintain stable fuel pressure under load
Larger fuel injectors – 380cc or 550cc options recommended to deliver the increased fuelling demands
Lohen Exhaust Manifold – precision port-matched to align with Lohen’s ported heads for optimal exhaust flow
Camshaft - your choice of camshaft will need to be added, we can install this to the cylinder for you prior to delivery if you wish, please request this at the point of order. We would recommend the Newman track PH3/4 camshaft.

These components help unlock the full potential of your head upgrade while safeguarding your engine under track or fast road conditions.

Key Benefits:

Fits MINI R50, R52, R53 One, Cooper, Cooper S, JCW & GP
Works with naturally aspirated and supercharged setups
No exchange unit needed – supplied outright
CNC machined ports and oversized Supertech valves
Port-matched compatibility with Lohen exhaust manifold
Ideal for performance builds, track cars, or high-powered road MINIs

MINI Gen 1 Engine Internals