Farnborough wrote: ↑27 Mar 2025, 09:27
venkyhere wrote: ↑27 Mar 2025, 07:28
Farnborough wrote: ↑26 Mar 2025, 23:44
This SF 25 conundrum appears to be around just how narrow that floor to ground dimension is. Notably effective in Aus practice, again China sprint Q and race, but they can't keep it there a whole race without plank risk.
Perhaps this discussion should be over in the car thread
Right, we have already raised (not literally
) this suspicion :
https://www.f1technical.net/forum/viewt ... 6#p1274916
I can see what you meant there (I read it when posted) but don't feel its related specifically to tyre contact patch as you noted.
It seems generally accepted though that a floor "landscape" or whatever we would call it, has a profound effect on whether the load is delivered in narrow spiked peak or broader more malleable envelope.
The peak type COULD give ultimate load, but create a very significant problem for the team's suspension experts in exactly how they can get it there, further to hold in that zone.
The opposite, with broader responses in floor, may ultimately mask suspension absolute performance by simply making less concise demands. This such that a competent suspension performance could be judged as very good or exceptionally poor (the same system) depending on which floor it's given to work with.
I suppose that's saying, if they don't fully understand the floor, then almost impossible to match that with mitigation in suspension, whatever the skill level they have invested in tbat department.
Edit to add:- this car does appear to possess good performance, at that lowest level. That's clear in evidence we've seen so far, particularly in China SQ & S as it easily held sway throughout. Full race pace, in the two so far, no not for that setup snd duration.
Perhaps I should have elaborated my post in the car thread, better.
While we both are in agreement that there seems to be a mis-marriage between the floor and the rear suspension, there seems to be disconnect in our perception of the tyre contact patch.
From my view, the softer suspension need is not related to 'load' pressing the wheel down, but rather from the camber change on the outer wheel from roll and creation of a 'bigger' contact patch, when car is under yaw in a corner, inorder to help traction AND tyre durability.
Slightly softer vertical and roll stiffness (without sacrificing pitch and heave stiffness), diminishes the negative camber and creates a nice 'pulp' of outer rear tyre, that allows earlier application of throttle and good traction from a 'bigger' contact patch. We can see this behaviour from the oboards of chasing cars when Ferrari is in front, the traction from exit of corners is very good (I suspect McLaren too has the same 'suppleness' in their rear suspension - not mad stiffness, granting them the same traction advantage).
Such 'adding softness' to the rear will inadvertently need to allow for greater vertical movement of the floor (under yaw, while the car is rolling), which in turn will impose a lower limit on how little the static ride height the car can have, otherwise the skidplate/plank will rub more than allowed.
The Q then becomes what kind of 'demand' the floor should make on the suspension - more leaning towards peaky and asking a "lot" of compression or more leaning towards 'spread' and not ask the limit of spring compression ? That will define the 'base setting' for the entire season with this car, unless some 'upgrades' change the aero or suspension maps. This being a chicken-egg problem (floor defines suspension or suspension defines floor), my wild guess is that Ferrari got their tradeoff equations wrong somewhere along the way and found out the hard way in the dry and with full tank of fuel, not in China, but in Bahrain itself. Perhaps Hamilton's 'setup' within the window of 'allowable variations' around their 'base setting' exposed it (remember the aborted long run on the final day of testing) and LeClerc's 'setup' didn't. They must have found a way to 'deal with it' by making changes between testing and the first race. However, in China, Pirelli torpedoed them by pumping up the tyre pressure, and Hamilton's car again 'showed up' the plank problem, while LeClerc's didn't.
Either way, this is classic "F1" - they solved the problem (porpoising) when there is no 'yaw' and the floor is working at it's peak at top speed in a straight line (perhaps with heave stiffness, floor peak DF peelback etc) ; while this season it has come back again under yaw in the corners, when the 'final setup' takes it away from the base setting too much.
This is what leads me to conjecture - compared to the rest of the big teams, Ferrari might have slightly shallower tunnels, even if they aren't aiming for a peaky floor
(as we know, contraction ratio from floor entry to venturi and expansion ratio from venturi to diffuser exit defines the peak) and that has come back to bite their a&& in the form of static-height-sensitivity-of-downforce, in situ with their 'base suspension stiffness' defined by geometry/materials etc.
