Imo, even a reverse engineered j-79 is a very important and big step towards better engines, because it shows that iran is now more capable in the field of alloys and super alloys and can make materials that can sustain higher temperatures and conditions. And if it has a better performance than the original j-79s on the f-4 then the f-4s can be upgraded with this engine, and no one should think that the f-4 is useless no matter how much its upgraded, Turkey still uses it and has heavily upgraded it, and iran is doing the same, the plane can carry a huge payload and can be used in all kinds of missions, if it can be upgraded, renewed and overhauled then there is no reason to retire it.