Go to the Muscle Mustang and Fast Fords website, they did an article on dyno numbers with different heads on the same engine actually 4-5 different levels of engines and heads. I think you will find that box stock the afr makes more power and torque numbers across the board.
__________________ 93GT
347 ci. 10.50:1 comp. AFR185's, FTI custom cam, Typhoon RPM, 80mm Pro-M/ 4" power pipe, 24lb. inj., 70mm TB, Pro Mag rollers,190 pump,upr k-member control arms, strange struts,subframes,lca's, uca's,underdrives,3.73 gears, tri-ax, BBK shorties, h-pipe flowmasters. BFG DR's. Summit Alum rad.,dual Fans. | 
How much power difference between afr 185s and trick flow heads? 
