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which the Stage 1 calibration has been fully optimised for
• Crank sprocket machining for keyway
39% increase in air flow
OE level of finish
The latest version of ECUtek also provides additional functionality
Cat Back Exhaust [Mk7 Fiesta ST] Pistons which the Stage 1 calibrationThe mountune Cat Back Exhaust for mk7 Fiesta ST reduces back pressure and improves performance, whilst keeping cabin intrusion boom to a minimum. Designed and developed in the UK, mountune's cat back exhaust utilises a Helmholtz chamber design in the rear silencer. This helps cancel out unwanted frequencies due to the way in which the exhaust gas waves are reflected. Despite being more complicated and therefore expensive to manufacture, this design