ARP 100-9941 Stretch Gauge with Dial Indicator

The ARP 100-9941 is a precision stretch gauge designed for accurately measuring fastener elongation during installation. This tool is essential for determining correct preload in rod bolts and other critical fasteners where bolt length can be measured after tightening.

Key Features:

• High-accuracy dial indicator reads in .0005-inch increments
• Extra heavy springs ensure consistent, repeatable measurements
• Measures fastener stretch to verify proper preload without relying solely on torque values
• Includes heavy-duty insulated plastic carrying case for protection and storage
• Compatible with ARP fasteners and other precision bolts

How It Works:

Measure the fastener length before installation and monitor overall length during tightening. When the bolt has stretched the specified amount per manufacturer guidelines, the correct preload has been achieved. This method is more accurate than torque-only installation, as it accounts for variables like thread condition, lubrication, and material properties.

Professional Best Practices:

Maintain a log of all fastener measurements before and after installation. Replace any fastener that shows permanent elongation of .0005 inches or more, or exhibits any deformation. This stretch gauge is a must-have tool for professional engine builders and serious enthusiasts who demand precision and reliability.