Quick question, it may have been asked but i couldn't find it
Does the engine manufacture order change? i.e will the best stay the best season to season? or is there a 'new formula' effect from time to time which changes the order?
the order stays the same, in that they will cost the same amount, season in, season out. But their stats change every season. There's a random element to it, but the likelihood is that they will still be in roughly the same order every season.
So Facami will almost always be a top 3 engine. But there is no guarantee that it will be the best every season, just that it's the most likely to be the best.