I identified the issue in a subsequent post. I wasn't shifting when the steering wheel lights go into the blue, which happens well before hitting the engine rev limiter. So I didn't get most out the KERS system before I noticed my mistake.
I don't know why the SF15-T would work better with the automatic shifting assist because it uses a hybrid system roughly similar to that of the SF70H. The F138 isn't a full on hybrid car though. It only utilizes KERS when pressing the assigned button, so it's a conventional layout where upshifting is preferable around the RPM redline.
But again, give manual shifting a go. Then when you get comfortable driving manual you can also consider switching off the auto blip assist, which adds an extra control element on cars not using an electronic kicker for rev-matching (typically older cars with a clutch pedal).
I suppose that is how the real car is. It's not like it's undriveable or anything, but simply particularly unforgiving.
I haven't checked the top speed of the 288 GTO, which reminds me that AC needs a proper straight for testing top speeds. The Nordschleife back straight is too short and the flat out section on Highlands Long is unreliable for being downhill. Where are you Mulsanne straight?
The in-game specs for the 288 GTO saying it can reach 305 km/h are probably not right. Over the years I have seen nothing to suggest it will exceed 290 km/h without some serious effort. On the subject of top speed, is the 330 P4 going fast enough in AC?
I noticed that the 812 has some bouncy revs on downshifts. Nothing major but enough to make me wonder if it's working as intended. It's not as bad as what I have previously noticed on the R34 Skyline, but what does everyone think?
I'm also sure it is, hence the reason why I compared it to the F40 being relatively similar in this regard. But the long default gearing of the 288 GTO really does raise an eyebrow at first, maybe because it doesn't accelerate as quickly as the F40.