On the general state of affairs of being a customer team in F1 today:
Nowadays it is possible for a customer team to win the world championship. I think with the sort of engine homologation that you've now, you've got to have the same engine for three years, and with the rev limit, with all the various things that are applied, I think that the differences between the engines are now very small.But also it makes it almost more expensive for you. In Ferrari's case, they're supplying three teams including their own. What you would normally do in the past is you would have an update on your engine, and on the customer team you would be one or two specs behind. And that makes sense because it also means that when you get updates you can use up all the old parts in the customer engines etc. etc. Well that doesn't make sense anymore because you would then have to homologate three different engines. So actually it's much cheaper for someone supplying a customer to make the same engine that they do for their works team. Because if you have three different specs you have to have three different homologated engines. And of course you can't update them, so you're then producing three different types of parts and it would just be much more expensive. So I think that basically now, customer engines are identical to works engines. Therefore if you do a better job in the other areas you'll go ahead and beat them.
On why that may be the theory but in practice it may not be so easy:
In practice, the teams that are buying the engines tend to be the ones with smaller budgets. So it's unlikely. But I think that theoretically where it may have been very difficult in the past because you would have had 20 less horsepower, and typically an engine would be revving to 19,800 (RPM) or so and the customer's engine would be revving to 18,700, because that makes the parts last longer. Whereas nowadays none of that applies because you have a rev limit. So every once revving to 19. As I say, you've got the engine homologation so is just more expensive to make different bits. So I think that all the engines now are, or certainly all of Ferrari's engines are very similar.

