The NHRA Technical Department has released additional 2026 Rule Amendments. Unless otherwise noted in this document, these additional amendments will come into effect immediately. The 2026 NHRA Rulebook Amendments can be found on NHRARacer.com under Tech, then Rules.

These amendments include the following changes…See the latest amendments document for complete details.

• Pro Mod, Master Cutoff – Any NHRA solid-state electrical power cutoff permitted
• Top Sportsman, Fuel System – Added, “See General Regulations 1:5”
• Top Dragster, Fuel System – Added, “See General Regulations 1:5”
• Stock, Cylinder Head – Minimum valve stem size 11/32” unless OEM equipped with smaller
• Stock, Engine – Over bore maximum changed from 0.080” to 0.085”
• Stock, Wheels – Only one valve stem permitted
• Factory Stock Showdown, Engine – Over bore maximum changed from 0.080” to 0.085”
• Factory Stock Showdown, Tires (new section) – Defines tires rules
• Factory Stock Showdown, Wheels (new section) – Defines wheel rules
• Super Stock, Cylinder Head
  • Titanium valves permitted
  • Minimum valve stem size 11/32” unless OEM equipped with smaller
• Super Stock, Engine – Over bore maximum changed from 0.080” to 0.085”
• Super Stock, Wheels, Only one valve stem permitted
• Pro Stock, Master Cutoff – Any NHRA solid-state electrical power cutoff permitted
• General Regulations, Fuel Systems, Pumps/Valves – Carbureted applications exempt from fuel shutoff valve