Last few days there is news spread around that J-10B is entering service next year. If that is true, we will know what engine they put in production soon.
Ashi-ji, do you know why western companies do not worry about exporting engines - at least civilian ones to almost any nation. This is because
1. They make money
2. They know damn well that engines cannot be cloned
Either way these engines are on display to anyone who wants to see them. But Chinese engines do not even make it to airshows outside China. What is there to hide? I will answer that question. I think that Chinese are so hooked on not being shamed that no one wants to admit failures. And in the Chinese communist system anyone who brings shame will be punished and punishment by death or imprisonment is common for offences seen as inimical to the state. Therefore the Chinese will only gloat and boast about successes. They will never mention failures. Only Pakistanis believe that. Any nation that actually works on technology will know that there can be failures and will admit them.
There are political reasons in China that demand that the Chinese state shows only progress, prosperity and leadership. The communist party oligarchy takes credit for that. So China never has failures. All successes. Your engines are perfect. You fighters don't crash. Your nation has done in 1 year what the US took 40 years to do. Go tell that to the admiring Chinese people and your united partners in Tibet, Xinjiang, Pakistan and North Korea. They have an eager audience listening to you.