INFORMATION REGARDING HEADER TEATHERS
In 2014, all removable multiple piece exhaust collectors/stacks must be securely fastened with either an NHRA-accepted header tether or a minimum 1/2″ (half-inch) stitch weld located on each primary tube to prevent loss of collector/stacks during competition. A list of currently NHRA-accepted header tether manufacturers is available on nhraracer.com.
”After much discussion on the topic, it has been decided that on cars with a complete exhaust system (including but not limited to mufflers, hangers, flanges, etc.) that are securely attached to the vehicle, header tethers will not be required. All other exhaust systems must conform to the rule as written. The current 2014 rulebook will be amended to reflect this change.” nhraracer.com
Above is an example of exhaust collector tubing that will require a header teather.
Above is an example of exhaust collector tubing that will not require a header teather. Because it has a 1/2″ (half-inch) stitch weld on all four of the tubes into the collector, it does not require a teather. Note: the pipes do not have a weld every 1/2″, simply one 1/2″ weld.
On this example, a header teather is not required, because the pipes are welded 360 degrees to the collector.
ANY QUESTIONS can be directed to the Woodburn Dragstrip office at 503-982-4461