Brave ok. I think I’ve got it. I spent some time on Silverstone today and finished off with a 30 minute race with one pit stop. So I /think/ the main thing is to make sure the checkboxes for repairing damage and suspension are unchecked. Even if you’ve had an incident free time, I guess it tries to fix the normal wear and tear anyway. Seems to reduce pit stop by at least ten seconds iirc.
I also saw a video where someone says to try and time switching the engine off so that you coast in to your pit area. Obviously with the clutch in. I tried it and it seemed to work although I was a wee bit tentative and too slow I think.
You can also switch the engine back on (clutch in mind) mid pit stop. That way you can be ready to go as soon as you drop. I stalled, but it only cost me a couple seconds.
I did all of that, admittedly a little hamfistedly and came out in 16 th after stopping from the lead. By the end of the race I was first again, but only by about a second. Given how slow I was, I suspect that means that I need to up the AI, but the methodology for the pit stop is good. I should probably have been 4th or 5th.
Hope that helps. Would be good to hear if it works.