Ferrari SF-25

[wuzak]

Not sure if this helps:

[Scarbstech] The Mercedes-Petronas video series gives a look at the actual F1 gearbox. We often see the carbon outer case, this is now just a structural part. The actual gears/differential are inside in a self contained unit called a 'cassette'.

https://www.reddit.com/r/formula1/comme ... eo_series/

The rules for penalties have separated out the gearbox from the internal components it encloses. But, despite this, the same amount of components are permitted when talking about the outer casing mounted on the cars, as well as the cassette that houses the gear change and driveline components.

https://racingnews365.com/how-f1s-gearb ... g-for-2022

[Vanja #66]

Thanks wuzak! Fair enough, cassette or not, the casing remains a structural part for rear suspension and is still called the casing by all teams and reporters as far as I can tell

[FDD]

Thanks wuzak! Fair enough, cassette or not, the casing remains a structural part for rear suspension and is still called the casing by all teams and reporters as far as I can tell

Straightforward conclusion.

[Sevach]

https://autoracer.it/it/analisi-ferrari ... iche-serra

Sounds like the current SF-25 suspension simply can't be made stiff enough, doesn't support springs that can do that.
Recently we've also got Red Bull's TD Pierre Waché saying that they run their car basically without suspension.

[Farnborough]

Thanks wuzak! Fair enough, cassette or not, the casing remains a structural part for rear suspension and is still called the casing by all teams and reporters as far as I can tell

As I've said all along .... this takes the structural load for ALL of the rear components, inclusive of crash, wing mount, torsion bars, anti roll etc etc.

The experience they had in the Bahrain test of noting a gearbox "problem" but with no unreliability of the "gearset" seen at all .... indication of structural not transmission problems. The two separated as now noted.

[Farnborough]

Not sure if this helps:

[Scarbstech] The Mercedes-Petronas video series gives a look at the actual F1 gearbox. We often see the carbon outer case, this is now just a structural part. The actual gears/differential are inside in a self contained unit called a 'cassette'.

https://www.reddit.com/r/formula1/comme ... eo_series/

The rules for penalties have separated out the gearbox from the internal components it encloses. But, despite this, the same amount of components are permitted when talking about the outer casing mounted on the cars, as well as the cassette that houses the gear change and driveline components.

https://racingnews365.com/how-f1s-gearb ... g-for-2022

Thank you for this contribution, obviously in accord with my description in this thread.

[Farnborough]

https://autoracer.it/it/analisi-ferrari ... iche-serra

Sounds like the current SF-25 suspension simply can't be made stiff enough, doesn't support springs that can do that.
Recently we've also got Red Bull's TD Pierre Waché saying that they run their car basically without suspension.

I've speculated (base on the comments emanating from team report) that once the "spring" rate is raised to a certain level, then the structure becomes vulnerable to that applied loading. That being just basic mechanical principle, but effectively losing control of system performance by doing so.

Also that CL had successfully made use of reduced spring rate and rocker geometry. Again from team report, but suggesting that setup starts to bring the suspension loads within structural performance envelope, but then unable to fully support the applied aero platform generated demand.

As they've noted, they're stuck between two unpalatable options. Latest report is for Silverstone arrival in dealing with this via new structure etc.

[venkyhere]

So the gearbox casing (structural member of the car) cannot take torsional loads if the suspension is stiff ?
How did this happen ? revised packaging given the 'shorter gearbox casing' requirement. Where did that requirement come from ?
'driver needs to sit more rearwards'.

I am sure the customer teams - Hass/Sauber uses their own gearbox casing design or are using SF-24's version. How can a top tier 'factory team' like Ferrari with state of the art tech and facilities at their disposal, get something like 'mechanical structure' wrong ? It's too basic a mistake. As a fan, I am boiling over, what must Elkkaan be feeling ? This is utter nonsense.

[leblanc]

So the gearbox casing (structural member of the car) cannot take torsional loads if the suspension is stiff ?
How did this happen ?

I think Vanja's speculation that the initial SF25 work by Cardile with regards to the gearbox case was not revised as the suspension design was advanced is most likely. Stupid things happen for stupid reasons. Gearbox case design complete? Sure! Check! And, they moved on. That's the simplest answer.

[leblanc]

I've speculated (base on the comments emanating from team report) that once the "spring" rate is raised to a certain level, then the structure becomes vulnerable to that applied loading.

Which structure? Just so I'm clear. The gearbox case or the chassis?

[wuzak]

So the gearbox casing (structural member of the car) cannot take torsional loads if the suspension is stiff ?
How did this happen ? revised packaging given the 'shorter gearbox casing' requirement. Where did that requirement come from ?
'driver needs to sit more rearwards'.

I am sure the customer teams - Hass/Sauber uses their own gearbox casing design or are using SF-24's version. How can a top tier 'factory team' like Ferrari with state of the art tech and facilities at their disposal, get something like 'mechanical structure' wrong ? It's too basic a mistake. As a fan, I am boiling over, what must Elkkaan be feeling ? This is utter nonsense.

Haas use the entire Ferrari rear end, suspension and all.

Sauber did until a couple of years ago. They've changed now as they will need to make their own gearboxes for teh Audi PU.

[ringo]

Thanks wuzak! Fair enough, cassette or not, the casing remains a structural part for rear suspension and is still called the casing by all teams and reporters as far as I can tell

Indeed.
The cassette is just the modular gearset package. That cassette is still fixed to the casing, otherwise it would rotate once the engine applies torque to the shafts. All structures are rigidly connected. Only moving parts a free to turn as they should be.
There seems to be little news leaks about new mechanical parts. Seems as was mentioned, they are bigger or allow more motion or adjustment.
I think Ferrari have a very clear understanding of the performance deficit which is a good thing.

I had discussed about ride height control for the ground effect in 2022 with a theory of a rod to bell crank connection where at a certain rideheight the crank is at a position where it imposes zero moment arm onto the springs, leaving the chassis to be suspended against a heavily damped material with much higher spring rate. When the direction is reversed, the crank angle changes and the moment arm increases and the spring re engages and provides resistance and the chassis is normally sprung again.
It's possible Ferrari could not achieve something like this with their current suspension.
If what I am saying is off the mark, the point I am making is the teams have some kind of trick to over damp the platfilorm at critically low rideheights, and Ferrari's wrong step is preventing them from exploiting it.

[Brahmal]

Haas use the entire Ferrari rear end, suspension and all.

I wonder if that had anything to do with them botching the Aus GP? It was described as a technical problem that they failed to pick up in testing IIRC.

[wuzak]

Haas use the entire Ferrari rear end, suspension and all.

I wonder if that had anything to do with them botching the Aus GP? It was described as a technical problem that they failed to pick up in testing IIRC.

Haas opted to keep last year's front suspension, which was the same as the Ferrari SF-24.

I think they took the SF-25 gearbox and suspension assembly, but I am not certain.

There could be some mismatch between front and rear for Hass if that is the case.

[Farnborough]

I've speculated (base on the comments emanating from team report) that once the "spring" rate is raised to a certain level, then the structure becomes vulnerable to that applied loading.

Which structure? Just so I'm clear. The gearbox case or the chassis?

The rear "outer" structure holding the suspension components, not the gearbox holding the gears.

There's very good clue in this aspect given at Bahrain test. There was concern over gearbox "problem" at that point. But importantly there's been absolutely no record of gearset/transmission failure or otherwise changed (short service life) that we've seen so far this season. Its a projection, but one that indicates this component is not compromised by variance in it's local structure to raise or compromise tolerances within it's components.

That is specifically separated for load it seems from any effects they are sering in regard to suspension integrity.

I'm commenting from the structures I've observed first hand and NOT the record out in public space. The rear "structure" is effectively a carbon dominated monocoque as is the primary front driver monocowue construction. Taking all of the load from suspension, wing, floor etc, etc as core duty and not the "traditional" gearbox taking the drive from PU to drive shaft output. This is the contemporary design used and primary difference to units commonly in place before gearbox penalty was in place.
It's an important delineation .... as I've repeated a few times ... which allows the gearbox components controlled by that penalty system to be retained and fitted to a replacement "exoskeleton" in event of accident damage resulting in suspension pickup location failure through impact.