4" shorter than the 74-Series

While we highly recommend replacing or upgrading your VANOS oil pump

Maintains full use of Valvetronic and Dual VANOS for great throttle response and wide power band

Horsepower: 460 - 850

CR330026 - CR330027

B46 Combustion Chamber Upgrade Service S85 Rod Bearings 4" shorter than the 74-SeriesPlease note that pricing is based on the customer providing a core. If you need assistance sourcing a core, contact our sales team. For enthusiasts and builders pushing the limits of BMWs B46 engine, optimizing the combustion chamber is a critical step toward maximizing performance and reliability. The 5150 Combustion Chamber Upgrade Service reshapes the combustion chambers using state of the art 5 axis CNC equipment for improved flow, consistency,