Bourne HPP K24 Block Coolant Diverter

The essential K24 component that is becoming impossible to find, now engineered and manufactured in-house by Bourne HPP.

If you are building a Honda K24 engine, the Coolant Diverter (Replaces Genuine Honda 11103-RAA-A01 Partition Plate) is not optional. With Genuine Honda stocks dwindling and lead times increasing, engine builders are often left stalled. We solved the supply chain issue by reverse-engineering the OEM design to create a precise, 3D-printed motorsport replacement.

Why You Need This Part

This component inserts directly into the K24 block’s water jacket. Its job is to manipulate the flow of coolant, forcing it to travel the full length of the block to cool Cylinders 3 and 4.

Without this diverter in place, coolant follows the path of least resistance, bypassing the rear cylinders. This results in:

• Thermal Instability: Dangerous "hot spots" at the rear of the block.

• Detonation Risk: Increased likelihood of knock in high-load scenarios.

• Warping: Uneven thermal expansion can lead to head gasket failure or warped heads.

The Bourne HPP Advantage

We don't just sell parts; we build championship-winning engines. When we couldn't source these plates fast enough for our own race builds, we manufactured our own.

• Reverse Engineered Precision: Scanned and modelled directly from a brand-new Genuine Honda 11103-RAA-A01 unit.

• High-Grade Manufacturing: 3D printed using heat-resistant, durable polymers designed to withstand the harsh environment of a race engine's water jacket.

• Direct Fitment: A drop-in replacement that requires no modification to the block.

Technical Specifications

• Bourne Part Number: BHP-K24-11103

• Replaces OEM Part: 11103-RAA-A01 (Plate, Partition)

• Material: High-Temp Motorsport Polymer (3D Printed)

• Fitment: All Honda K24 Engine Blocks (K24A, K24Z, K24W)