The Enginetech EM4521 exhaust valve features a 1.103" head diameter, .2150" stem (.2150 nominal), and 3.8032" overall length with a nitride-hardened stem. Fits 2014-2018 Subaru 2.0L/2.5L applications.
Important Notes
- Sold individually as a single valve. Order the quantity required for your engine configuration (typically one per cylinder per valve position).
- Nitride-hardened stem surface resists wear and galling in high-temperature and high-load applications.
- Always verify head diameter, stem diameter, overall valve length, and groove count against the OE valve being replaced before installation - valve dimensions vary across engine families and a visual match alone is not sufficient.
Specifications
| Part Number | EM4521 |
| Valve Type | Exhaust Valve |
| Head Diameter | 1.103" |
| Stem Diameter | .2150" (.2150 nominal) |
| Valve Length | 3.8032" OAL |
| Stem Finish | Nitrided Stem |
| Number of Grooves | 1 |
| Weight | 0.25 lbs |
| OEM Cross-Refs | Topline: EVSU16F |
Vehicle Fitment
2014-2015 Subaru 2.0L / 1995 DOHC H4 16V FB20 84.00mm Bore; 2014-2018 Subaru 2.5L / 2498 DOHC H4 16V FB25, BA, BC 94.00mm Bore.
Product Video
Watch the Enginetech exhaust valve overview: https://youtu.be/G487Dw8HtII
Watch the Enginetech exhaust valve overview: https://youtu.be/eLaQHop7rH8
Enginetech standard valves are stock-replacement engine valves produced from OE grade materials or better, engineered with the production engine rebuilder in mind. Face runout, stem finish, and stem diameter tolerances are held to some of the tightest standards in the internal engine parts industry, and every valve is inspected by on-site engineers against a documented quality plan before it leaves the plant. The line covers domestic, import, and common high-performance applications across a full range of head diameters, stem diameters, and overall lengths, with chrome-plated and nitride-hardened stem finishes available where the engine's operating conditions call for the upgrade. Always verify head diameter, stem diameter, valve length, groove count, and any oversize stem requirement against the original valve being replaced before installing, as multiple valve configurations can share the same vehicle nameplate.
WARNING: This product can expose you to chemicals including lead and nickel, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.P65Warnings.ca.gov.
