AR3-GP wrote: ↑
Sat Apr 01, 2023 10:05 pm
gandharva wrote: ↑
Sat Apr 01, 2023 9:49 pm
As we are talking about kinetic energy, the whole system needs to be able to handle this higher forces. Crankshaft, gearbox and so on.
So it's clearly not just software. Their H might also be better than the competitors, but this has no direct influence on the drivability under braking.
You started out by emphasizing how aggressive MGU-K retardation mapping is the key to RB's advantage. This problem is more trivial to solve than the MGU-H. MGU-K retardation is primarily software, which is why RB can ask max to go to different maps.
Then you suggest even this is not so trivial because of the forces to consider. The ICE alone outputs 700 hp to the crankshaft. The maximum MGU-K recovery is 120Kw or roughly 160hp. The forces generated by the recovery are smaller than that generated by the ICE at full throttle. Of course you have to consider that the torque in the gear train goes the opposite direction but I don't think this requires anything special that other teams are not aware of. The harvesting forces themselves are just software. Clearly RB is not executing it as well as other teams.
I agree on your point that clearly MGU-K harvesting would cause the driveability compromise but that's a different point to make, as opposed to implying the MGU-K harvesting is where the Honda PU advantage lies. From my understand, the MGU-H is where the Honda superiority comes from. That in addition to having an efficient, low loss, MGU-K.
The comments made recently by MV about rear locking, then slow down change etc seem to indicate more usage of recovery and engine brake effects than generally discussed. There's substantial advantages I believe, but that's dependent on driver adaption/style to accommodate this.
Braking through the diff is fundamentally very different to rear brake via disc. The disc has parity across the axle, making it more difficult for front grip in turning the car, rear bias may help but still equal across the two tyres.
Through the diff though (no secret but likely considered older technique) as the input to diff shaft is braked through engine torque or recovery, then with the diff locking percentage backed out at corner entry phase, will cause the inside wheel to travel backwards, that's in relation to the outside wheel THIS IS IMPORTANT. The affect of this is to brake the inside rear wheel to steer the vehicle into the corner from braking bias.
Note, this isn't a secret mode or hidden facility, but something most every rally driver will do, and probably more noted as pure technique in day's of H pattern gearbox particularly at places like Monaco where downshift could easily skip ratio to drag the car toward tight apex.
How that could be applied currently, with driver behaviour, is to ramp up the recovery through initial phase of heavy braking, then supplement this with very late and very fast down changes to keep that retardation high through the differential. Running friction brake bias trim to accommodate date this would be particularly useful.
If driven like this, the car has significant potential advantages in entry to high braking corners. Those situations when MV gets down inside another car but still turns it, would be one area to maximise this. Often now labelled as "dive bombing" the RB holds significant advantage there it seems, to the surprise of others.
Evidence suggests that with DR it was an attribute tgat was there even then. Current drivers ability to hone this is important. Notice when CL was chasing SP at Imola last year, entry into first chicane when it looked like CL was lining up a pass, then entering the brsking phase and tge Ferrari seemed to go backwards.
Also the pass on LH at Circuit of the Americas at the end of back straight last year.