2002-2006 R50 MINI Cooper and R53 Cooper S Hatchback
2005-2008 R52 MINI Cooper and Cooper S Convertible
Stage 1 Ported Head
Designed specifically for street driven MINIs, the Stage 1 Cylinder Head package maximizes torque and HP within the portion of the powerband you spend the majority of your time driving in. The result is a smooth and broad power delivery. Tested for maximum performance, this ported and polished head uses stock valves and springs. Works great with the performance camshaft upgrade NME6045.
Air flow in the Stage 1 Cylinder Head is increased an incredible 20% without sacrificing port velocity. Intake-exhaust interport relationship is also optimized for maximum power with efficiency. The combustion chamber has also been reprofiled for improved combustion properties.
Depending on parts used in conjunction with this Cylinder Head package, power gains are potentially in the 20-30 horsepower range. We recommend larger injectors when using this head.
Stage 2 Big Valve Head
The Stage 2 Cylinder Head includes the Stage 1 porting and adds larger valves, 3 angle valve job, and match port intake, works great with a performance camshaft upgrade.
This head uses our NME6026 Valve Set with +0.5mm oversized Intake Valves and -1.5mm oversized Exhaust Valves.
For Head and Cam packages, see NMK1285.
There is an additional CORE CHARGE which will be refunded when we receive your REBUILDABLE core. Heads with cracks, severe warpage, piston to head contact or any physical defects WILL NOT QUALIFY for a refund. Core must be complete and fully assembled with cam, rockers, and valve assembly.
Allow 2-3 weeks for delivery. These heads are made to order.
TECHNICAL DISCUSSION: AIRFLOW DYNAMICS
The total air flow through a gasoline engine determines its maximum horsepower. At peak power, a racing engine will use 1.67 cubic feet of air (CFM). To increase power output, either the air flow capacity must be increased or the air/fuel mixture charge must be burned more efficiently.
The flow bench is a measuring device designed to measure the air flow capacity of various engine components. Air is blown or sucked through the engine at standard air pressure and the air flow capacity is measured. In this manner, different parts can be compared and the effect of changes can be evaluated. The flow tests are conducted at constant peak air velocity, usually between 100 and 400 feet per second.
Additionally, an engine's efficiency and power can be increased considerably by taking advantage of natural dynamic effects which occur during the intake cycle. Both kinetic energy and resonant pulses can be harnessed to fill the cylinder with mixture. When the inlet closes, a pressure pulse bounces back out the intake track. By making intake track the proper length, the returning pulse can be timed to arrive at top dead center of the next cycle, pushing extra air in and keeping exhaust gas out.
Check local regulations on conformity for street use.