(see Fittings & Adapters)

Ferrea’s high-performance BMW N54 valve springs ensure your engine handles increased lift and RPMs without issue

Retainer: RET-BM2521/T1S-LC

Boost by gear support for optimized performance

or competitive track use

BMW S58 Port Injection Kit 130612 (see Fittings & Adapters)RK Autowerks Port Injection Kit for BMW S58 Engines The RK Autowerks Port Injection Kit is designed to meet the demands of high performance S58 builds. Whether you're chasing big horsepower or seeking to maximize fueling efficiency, this kit delivers reliable results without compromise. Precision CNC machined and tested in RKs Texas facility, each component reflects the brands commitment to engineering excellence. This kit is fully compatible with