1JZ / 2JZ – Billet Upper Water Neck – Race
 
Built for high-performance cooling systems.

The Ichiban Engineering Billet Upper Water Neck – Race Version was developed specifically for high-horsepower 1JZ and 2JZ engine builds running external electric water pumps and custom AN cooling systems.

Unlike the restrictive OEM cast housing, our Race version was engineered from the ground up for
maximum cooling flexibility, improved reliability, and clean motorsport-style plumbing.

Precision CNC-machined from 6061-T6 aerospace-grade billet aluminum, the housing delivers exceptional strength, corrosion resistance, and long-term durability under extreme heat and pressure conditions commonly seen in drag racing, drift, and circuit applications.

Version 2 introduces several major improvements, including upgraded sealing and optimized fitment. Most notably, the flange connecting to the OEM intake side now features an integrated O-ring sealing system, eliminating the common coolant leaks associated with factory paper gasket designs and aging OEM water necks.

The outlet features a large ORB-threaded connection, allowing the use of either AN16 or AN20 fittings depending on the cooling setup requirements. Two integrated auxiliary ports are also included — one for coolant temperature sensors and another dedicated turbocharger coolant feed
port.

Designed specifically for external electric water pump configurations, this Race version is ideal for serious turbocharged JZ builds requiring maximum cooling system flexibility and reliability.
For vehicles retaining the OEM mechanical water pump setup, please refer to our separate Street Version listing.

Key Features
• Designed for Electric Water Pump Setups
Ideal for high-performance JZ builds running external cooling systems.
• CNC-Machined 6061-T6 Billet Aluminum
Manufactured from aerospace-grade billet aluminum for superior durability and precision.
• Version 2 Improved Design
Updated sealing and modular cooling layout improvements.
• Integrated O-Ring Seal
Eliminates common coolant leaks associated with OEM gasket-style housings.
• ORB Outlet Configuration
Compatible with AN16 or AN20 fittings for flexible cooling system routing.
• Integrated Auxiliary Ports
Includes ports for coolant temperature sensors and turbo coolant feed lines.
• Motorsport Cooling Solution
Perfect for drag racing, drift, time attack, and high-horsepower turbo applications.
• Custom Anodized Finishes Available
Available in multiple anodized colors to match your engine bay.

Built for serious JZ cooling systems.

The Ichiban Engineering Billet Upper Water Neck – Race Version delivers the strength, sealing reliability, and cooling flexibility required for modern high-performance 1JZ and 2JZ engine builds.

⚙️ Fits Toyota 1JZ and 2JZ engines
⚠️ Designed for external electric water pump applications
📧 For technical questions or custom requests contact sales@ichiban.engineering