Also, merc has a clever K-shutoff system which kills K power after a certain speed has been reached. Very obvious watching onboards in spa and monza. They would reach 330 kph, then suddenly start to drop few clicks before the braking zone. So they in effect sit on much higher speeds for much longer periods, but then because of the shut off clock slower trough the speed traps.
That's called allocation. The mgu-k is only to have an output of 4MJ; you need to spread that in an optimized way. I presume at 330kph the k power will be offset by the drag. I'm pretty sure Renault and Ferrari do the same thing.
What? Just look at speed trap data lol. This is not DRS rev limiter era anymore when RB was slow in the speed traps, but still actually got to the end of them faster because of better acceleration. If you're 10 clicks slower now, you're losing troughout the whole straight, not just last 100m.
I believe that there's a deficit, I don't believe the deficit is 75bhp which translated in over a second a lap.
Also, There's a general misconception floating around that RB with those low wings in monza was actually quicker down the straights than merc or williams because of the infamous tv graphic showing ricciardo doing 362, which couldn't be further from the truth. Hamilton did 361 behind massa very early in the race and then sat on that number for some time even when he pulled out of the slipstream.
And here comes the issue of allocation again. As said before, for the optimum laptime you need to spread the 4MJ. However for overtaking you probably want to have the extra power above the normal cut off point. Is it possible to reach 362kph? Possible if you allocate a big part of the 4MJ on just one straight. I'm not saying that this what happened, just that this is a possibility.
So we're back to square one. It's the engine.
No we are not since that changes the picture. Horner is incorrect to say they have 75bhp deficit, since the biggest issue is the harvesting. Going from a 750bhp PU to a 825bhp PU will not change a thing if they don't increase harvesting efficiency.