RB26 Sump Extension Kit

Name: RB26 Sump Extension Kit
Brand: HPR Tuning
SKU: HPR-RB-SMP_EXT_K

HPR Nissan RB26 Billet Sump Extension Kit

Increasing the oil capacity of the RB26 wet-sump system is essential for engines using high-flow oil pumps and seeing high-cornering, particularly in high-performance street and track applications.

The HPR RB26 Billet Sump Extension Kit is a complete wet-sump upgrade combining modular billet sump extensions, CFD-developed baffling, and a reinforced front differential cover. The system increases oil capacity while retaining the factory oil-pan height and original oil-pickup arrangement.

Features and Benefits

Approximately 50% increased oil capacity
Improved oil supply during hard acceleration, braking, and high-G cornering
Billet modular design with removable sump extensions
Retains the factory oil-pan height
No custom oil pickup required
CFD-developed internal oil-pan baffling
Reduced cutting and welding compared with many alternative solutions
Designed to reduce installation and fabrication time

Modular Billet Sump Extensions

The kit uses two removable billet aluminum sump extensions to increase oil capacity evenly on both sides of the factory oil pan.

Baffled weld-in flanges control oil movement between the factory sump and the added-capacity sections. The modular design also allows the extensions to be removed for inspection, servicing, or future maintenance. Cutting templates are included to simplify installation and ensure accurate positioning.

RB26 Oil-Pan Baffle Kit

The HPR RB26 oil-pan baffle kit was developed using full-scale computational fluid dynamics simulations representing the extreme acceleration and cornering forces experienced during track use. The baffle retains the approximate height of the factory baffling and incorporates internal edges designed to trap and retain oil around the pickup. A Z-shaped upper plate helps prevent oil from moving away from the sump under hard acceleration and redirects it toward the pickup area.

The kit uses Improved Racing trap doors specifically designed for fluid baffling. These maintenance-free doors feature a 60-degree stop position and provide significantly less flow resistance than conventional rubber trap doors.

Reinforced RB26 Front Differential Cover

The included HPR front differential cover is CNC-machined from 6061 aluminum and anodized for increased durability and corrosion resistance. The cross-sectional thickness of the cover has been doubled, while the bolt-hole clearance has been reduced to help eliminate unwanted movement and reduce the risk of cracking around the front differential housing.

The oil filler and drain-plug locations have been repositioned to provide clearance for the HPR sump extensions. The cover can also be used with a factory RB26 oil pan without the extension kit.

Included Components