DescriptionRK Autowerks is home of the fastest S58 — 7.77s at 184 mph — and the first to break into the 7s. This forged engine build reflects that same standard of performance.Designed for B58 and S58 platforms, the RK forged long block delivers high-strength internals, proven hardware, and build flexibility. It includes CP Carrillo rods, ARP 625 head studs, RK HP bearings, and a full long block assembly — cleaned, sealed, and ready for power.You can select optional upgrades like CP pistons, stroker kits, fire rings, CNC headwork, and oversized studs — with matching install service available.Key Features • Forged internals rated for high boost and power • ARP 625 head studs and ARP main studs included • Full RK-spec long block assembly • Add-ons for pistons, sleeves, CNC head, cams, and more • Install service and domestic crate shipping optionsTechnical Specifications Material: OEM block with forged internals and RK-spec bearings Construction Method: Assembled long block Compatibility: B58 Gen 1, B58 Gen 2, S58Applications • B58 Gen 1 – 340i, 240i • B58 Gen 2 – Supra, M340i, M240i • S58 – M2 G87, M3 G80, M4 G82/G83, X3M F97, X4M F98Installation and Support A $4,500 deposit is required to begin your engine build. After placing your order, we’ll follow up to confirm your configuration and next steps.Installation at RK HQ is available for $5,000. Crate shipping both ways (within the U.S.) is $800. International shipping options available upon consultation. Core is required — either sent in advance or charged at market value.Why Choose RK Autowerks Our engines are backed by track results — not just theory. We’ve built the fastest and most consistent S58s out there, and every RK engine reflects that experience. We test what we build. We race what we sell.Warranty Click Here For Warranty Info
