BMW N54 & N55 Spool Helix HPFP Overdrive Unit

The Spool Helix overdrive unit is a planetary gearbox that spins the N54 and early N55 high pressure fuel pump faster, so it can keep up with tuned power levels.

Why you need it

When tuned, the factory HPFP can't pump fuel as fast as the injectors use it, so rail pressure drops. The Helix uses a ring gear, planet gears and a sun gear to raise pump shaft speed and add delivery strokes per cycle, increasing displacement without adding a port injection system. Spool's testing found overdriving the pump did not worsen its known failure modes.

Fits

• BMW N54
• BMW early N55

Features

• Planetary gear overdrive for the factory HPFP
• Supports up to 600 whp on full E85
• Supports 750+ whp on E60 mixes
• No secondary port injection needed

What's included

• Billet vacuum cover
• Mounting plate
• Support bracket
• All installation hardware
• Helix 10-micron filter unit (if selected)

Good to know

Choose N54 or N55 and whether to add the Helix 10-micron filter unit. Tune changes are required, and Spool works with the major tuners to supply calibration changes. Professional installation is recommended.