NSW 9-Inch Water-Brake Dynamometer

High-Performance Automotive Water-Brake Absorber

The NSW 9-inch platform is designed for serious automotive, racing and engine-development dynamometer applications.

It is available in single- and dual-rotor configurations.

NSW 9-Inch Single Rotor

Current NSW 9-inch single-rotor capability is approximately:

450+ HP

325 lb-ft

Maximum approximately 14,000 RPM

This combination makes the 9-inch brake suitable for many naturally aspirated, turbocharged and high-RPM automotive engines.

Water-Pump Sizing

For a system intended to use the full approximately 450 HP capability, the conservative NSW large-system pump guideline gives:

450 × 0.15 GPM ≈ 67.5 GPM

A pump capable of approximately 70 GPM at suitable operating pressure is therefore a reasonable high-capacity starting point.

This does not mean the brake will always consume 70 GPM.

Actual flow depends on:

engine output
RPM
valve position
water pressure
pocket fill
duration of the pull
Dual Rotor

The 9-inch dual-rotor brake significantly increases hydraulic interaction area and is intended for applications requiring substantially greater absorption than the single-rotor version.

The pump, valve and plumbing must therefore be sized for the actual dual-rotor application.

Water Control

For repeatable testing, NSW recommends a stable regulated supply feeding a manual or automatic load-control valve.

A typical system is:

Reservoir → Pump → Regulator → Auto-Load Valve → 9" Brake → Discharge

Applications

Suitable applications include:

turbocharged automotive engines
naturally aspirated racing engines
rotary engines
high-RPM six-cylinder engines
development and endurance testing