Fresh RB25 / RB26 2.6L Forged Short Block Street & Performance Build Foundation

Built for RB Enthusiasts Who Want Reliability, Proven Components & Strong Street Power

If you’re chasing a strong, responsive RB build without cutting corners, this freshly assembled RB25/RB26 forged short block is a serious foundation for a street or performance engine package.

Built around an RB25 RWD block with a full RB26 rotating assembly, this combination gives you the packaging and functionality of an RB25 while increasing displacement to approximately 2.6L for improved torque, response and overall drivability.

Whether you’re building a tough street car, drift car, circuit package or responsive weekend warrior, this short block gives you a proven platform to build from.

Why This Combo?

The RB25/RB26 hybrid has long been regarded as great all-round RB combination, combining RB25 fitment and practicality with the slightly larger capacity of the RB26 rotating assembly and increased capacity of the RB26 platform.

This setup is ideal for buyers wanting:
✔ Strong street response
✔ Proven forged internals
✔ Reliable power capability
✔ A professionally machined base to finish their own combo
✔ Flexibility to spec their own oiling and cylinder head package

Build Specifications

Bottom End

• Re-worked RB25 RWD block, suits 2 wheel drive applications.

• Used, reground RB26 crankshaft

• Crank oil pump collar fitted and grub screwed

• New Spool forged connecting rods with ARP bolts

• Used CP 86.5mm 9.0:1 compression forged pistons (dyno time only)

• New ACL race bearings

• New ARP main studs

• ARP Main stud kit.

Machining & Assembly

• Freshly bored

• Freshly decked

• Rotating assembly balanced

• Professionally installed repair sleeve in cyl #6

Included Extras

• Used genuine N1 oil pump included (good condition, unfitted)

• New water pump included (unfitted)

• Stock oil restrictors fitted (can be changed to suit application)

• Stainless welch plugs installed

• New Nissan rear main seal included (unfitted)

This is a quality short block foundation designed to allow the buyer to finish the package to suit their goals.

Frequently Asked Questions

Is this ready to run?

This is a fresh short block ready for your cylinder head and final engine assembly.

Is the oil pump installed?

No. A used genuine N1 oil pump in good condition is supplied unfitted, allowing inspection and installation during final assembly.

Is this suitable for 600HP?

Yes, with the correct supporting components and professional tuning, this combination is suitable for builds in the 500–700HP range.

What oil restrictors are fitted?

The block currently has stock oil restrictors installed, allowing the buyer to modify the oiling strategy to suit their intended build.

Is balancing completed?

Yes, the rotating assembly has been balanced.

Pick Up Welcome

Local pick up is welcome by arrangement.

This can be a great option if you'd like to inspect the short block in person prior to taking delivery.

Australia-Wide Freight Available

Freight is available throughout Australia.

As freight costs vary depending on location and whether delivery is to a residential or commercial address, please email prior to purchase for an accurate shipping quote.

We take care to package engine components appropriately for transport to help ensure safe arrival.

International Shipping Available

International shipping is available to any international sea port.

Freight costs vary depending on destination country and import requirements, therefore please email prior to purchase for a shipping quote before ordering.

Buyers are responsible for any applicable import duties, taxes, customs clearance requirements or local charges in their destination country.

Warranty & Liability

Short block carries a start-up warranty only.

Warranty coverage is strictly limited to the fitted parts listed within this advertisement only.

Warranty does not cover:

• Labour

• Time

• Towing

• Return shipping

• Investigations or diagnostics

• Gaskets

• Bolts or fasteners

• Fluids

• Seals

• Other components or associated failures

• Consequential damage

• Any consumables of any kind

• Incurred costs or outgoings of any kind

Any defect, whether visible or otherwise, must be reported and the unit returned for inspection and assessment to Boost Doc

Where return is not practical, Boost Doc reserves the right, at its discretion, to appoint a third-party inspector on its behalf.

This short block has been listed in good faith, accurately disclosing the components used and the machining and assembly work carried out.

Any rights under Australian Consumer Law that cannot be excluded continue to apply.