More on engine homologation and costs.
I worte previously about how engine homologation was not the answer to Formula 1's cost problems. To clarify, I wouldn't say that I'm any more in favour of a spec engine in F1 than I am in favour of an homologation period of several years for engine designs, but clearly something has to be done about costs and the engine represents a large part of the team budget that goes on something that makes very little difference. If you're going to effectively eliminate competition on the engine front, you might as well go all the way and some real benefits.
The real problem is that we now know too much. There was a golden era when smart people like Keith Duckworth (of Cosworth fame) could make considerable advances on a small budget (by current standards anyway). Now every advance is tiny and the cost ranges from considerable to increadible. As such you really have to question the point of continuing competition in englnes in motorsport. There isn't any category I can think of that allows for different engine designs without rules that constrain their development severely in the interests of safety or competition or costs. You could make an argument in the case of series like World Rally Cars or World Touring Cars where the car is ostensibly based on a production car, that the engine needs to be based on the model used in the production car. But that's not the case with Formula 1, Le Mans prototypes or many other forms of motorsport.