Familiarity with suppliers

I was told by a few people that it takes a certain amount of time for drivers to get to know engines and tyres etc. If thats not true then stop reading, however I accidently let my Murk engine contract run out at the end of last season and then offered too little to get it back, forcing me to run with a different engine for the first race of the new season before returning to Murk. This season i've had very little success despite having two very solid drivers and a car that was up there with the best, so i'm guessing my failures are to do with the engine cock up.

I accept the blame for not renewing the contract but using just one of my drivers as an example, he's ran 69/70 races for me with a Murk engine in his car. I can understand the first race being shit with a worse engine and no experience with it, but why should it take up to a season for my drivers to remember the feel of the car that the Murk engine gives? It's a decent feature but surely you should do it in the way of how many races you've had with x as a whole, not how many races in a row you've used it?

I don't think it is necessarily how many races in a row that it was used. It could be that the change in engine somehow effected the design of your car, and that it became less suited to the Murk engine for that reason? I'm not entirely sure how that works, or if it works like that though.

It could also be that the teams and drivers around you might be superior for reasons you're unfamiliar with. I had the same problem recently. I thought for a long time that the drivers I had were up there with the best, but it turned out that they were far from it, even with a car that was a good 10-20% better than those around me, and this was after finishing 2nd for a long time, and winning a Championship as well.

Like you said, it could be the engine mix-up, but it is more likely your drivers and/or other parts of your team that could be effecting performance in a bigger way. It might be worth taking some risks to find out if it is any of these.

There is no "way of understanding" the engine.
The engine won't get better the more races you drive with it or something like that.
Your problems are related to something different.

As far as I know this is definitely not true. It takes time to get used to a certain supplier

It doesn't influence race performance.
I can't find anything in the source code that would influence the performance or something else.

Sorry for the confusion, but simple familiarity with suppliers and their product does affect your race performance.  However this would not have a significant impact over the course of a whole season, only the first few races or so.

I think Jamie has the right perspective here.