BK is right, the NHRA rulebook states " Aftermarket axles and axle retention device mandatory on Top Fuel, Funny Car, Pro Stock, Top Alcohol Dragster, Top Alcohol Funny Car, Comp, Super Comp, Super Gas, Super Street, and 10.99 or quicker E.T. cars; also mandatory on any car (regardless of class or E.T.) with a spool." Looks like your combination should run somewhere in the 10 second range so aftermarket axle would be required. Lots of rules and requirements and most all are for safety:)
While you can get by with re-splined axles in a low horsepower and lightweight car, a full size doorslammer running the same times would surely abuse them. Same rule covers both situations so...