The High Speed Engineering RB26 81 mm EN26 Billet Oil Pump Gear Set is a high‑strength replacement for the fragile sintered gears found in early-model Nissan RB26DETT oil pumps. Precision‑machined from premium EN26 billet steel, this gear set provides exceptional durability, stable oil pressure, and the reliability required for high‑RPM and high‑boost RB engine builds.

This version is designed specifically for the early OEM RB26 oil pumps that use the larger 81 mm outer rotor. These early pumps are prone to internal gear failure and are considered a known weak point in modified RB26 engines.

Compatibility:

• Designed for early RB26DETT oil pumps
• Suits pumps using the 81 mm outer rotor diameter
• Correct pump identification: 8-bolt rear cover (7 perimeter bolts + 1 centre bolt)
• Not compatible with later N1 or revised OE pumps using 77 mm gears

Key Features:

• EN26 Billet Steel Construction: Provides extreme resistance to cracking, shattering, and fatigue under high RPM and heavy load.
• Precision CNC Machining: Ensures consistent tolerances, optimal tooth engagement, and stable oil pressure across the entire rev range.
• Direct Internal Replacement: Installs into the OEM early RB pump housing with no external modifications required.
• High-RPM Reliability: Eliminates the well-known gear failure issues of the early 81 mm pumps.
• Motorsport-Grade Strength: Suitable for drag, circuit, drift and high-power street RB26 builds.

Why Upgrade the Early RB26 Pump?

• Factory sintered 81 mm gears are prone to breaking at high RPM or during hard limiter use.
• Oil pressure fluctuations can lead to severe engine damage, including bearing failure.
• Billet EN26 gears dramatically improve pump strength and long-term reliability.
• Essential for high-power RB builds exceeding the safe limits of the OEM gears.

The High Speed Engineering EN26 Billet Oil Pump Gear Set for 81 mm RB26 pumps is a critical reliability upgrade for any early RB26DETT engine. Whether used for street performance, motorsport, or high‑boost applications, this gear set ensures maximum strength, stability and confidence at high RPM.

Notes

• It is the engine builders responsibility to ensure that all components are clean, undamaged and free running BEFORE and AFTER installation.
• Gears must be assembled initially with clean engine oil or assembly grease. Do NOT run dry!
• With the inner and outer gear sitting in front of you and the nose/seal diameter facing toward you, the outer gear should be laid over the inner gear with the “wave” profile in a clockwise orientation. The 2 wave “points” should be facing in the same direction (see assembly instructions).
• These gears are direct replacements for standard gears. If something doesn’t fit easily, then something isn’t right. You should not have to modify the housing and once installed, the gears should spin freely, with no restriction other than the oil seal.