Product Description
BMW S50 Race Series Engine Build - ZNM Performance
ZNM Performance Race Series Engine Build Program
Introducing our BMW S50 engine program—engineered for purists and track enthusiasts seeking a high-performance rebuild of BMW’s original U.S. and Euro-spec inline-6 from the early E36 M3 lineup. This page applies to all S50-equipped models, including the 1995 M3 (S50B30US) and European S50B30/B32 variants.
The BMW S50 features a robust iron block, aluminum DOHC head, individual throttle bodies (on Euro models), and strong tuning potential. Known for high-revving characteristics, the S50 can suffer from rod bearing wear, head gasket issues, and VANOS failures at elevated mileage or under track abuse.
That’s where our S50 engine build program comes in. Every engine is completely disassembled, inspected, cleaned, and precision-machined. We offer forged internals, headwork, and bottom-end reinforcement to ensure your S50 delivers reliable power whether naturally aspirated or boosted.
Our facility in Pompton Lakes, NJ builds engines for customers across the U.S. and internationally. All engines are fully disassembled, measured, and assembled in-house with final clearances precisely set by our team. Please inquire about international shipping options.
Key Features and Options for Our Built S50 Engines
- Forged pistons and rods for high-RPM NA or boosted turbo builds
- Block deck resurfacing and ARP 2000 or 625+ head studs for sealing integrity
- MLS or fire-ring head gasket options for high cylinder pressures
- ARP main and head studs for improved clamping under extreme stress
- Capable of supporting 300–350whp NA or 600+whp boosted with proper supporting mods
Cylinder Head Upgrades for Your S50
- Upgraded dual valve springs and titanium retainers for sustained high RPM operation
- Porting and polishing available to improve airflow on US and Euro head castings
- Valve seat reconditioning and guide inspection included in every head build
Bearing Upgrades for Your S50
- ACL or King XP bearings for increased load resistance at high RPM
- Clearances hand-set in-house for optimal oil film and bearing longevity
Frequently Asked Questions (FAQ)
Q: Can the S50 be built for boost?
A: Definitely. While originally designed for NA performance, the S50’s iron block and strong head architecture make it an excellent platform for turbocharging. With forged internals, ARP hardware, and standalone tuning, we’ve built S50s reliably making 600–700whp.
Q: What limits the factory S50 at high RPM?
A: Factory valve springs, rod bolts, and VANOS components tend to show fatigue near redline. Our builds upgrade these systems to withstand extended revs above 7000 RPM safely.
Q: Do you rebuild my original engine or supply a donor?
A: We typically rebuild your original S50B30/B32 or a donor core. If you don’t have one, we offer core sourcing and shipping coordination to support remote customers.
Q: Can I daily drive a Race Series S50?
A: Yes. Our Race Series S50s maintain OEM drivability while providing improved durability and performance. They’re ideal for dual-duty cars, spirited street builds, or race-prepped weekend machines.
