I'm not sure about the engine rules, but no one have any concrete evidence that Ferrari put the F1 engine in that car anyway. The best people can tell is that it's a turbo engine due to the sound. But Ferrari is free to develop any engine they wish outside of F1. Ferrari can claim they are developing a turbo engine for something else, and no one can prove otherwise. Unless a traitor inside the team leak out official documents that says they are testing the F1 engine
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