I'd guess Decker or Aaen side exit pipes but you can usually find a portion of the name stamped in the sections somewhere. :hmm:
Those are most likely improver pipes or even higher revs so you're looking at 9600 to 10200 RPM probably. Cut a couple holes in the side of the belly pan then put her...
Aeropsace designer working for ATK / Thiokol for a little over a year now. Used to be a product designer at tier one companies to Ford and Nissan for almost 15 years previously back in Michigan.