Ok well you’ve rated me negatively and still seem to think it’s closed on the Ferrari - I guess the gifs aren’t working for you or something.
The first part of thisCedo wrote: ↑23 Feb 2019, 01:16Here is Marc Priestley explaination to someone asking him what going on with the Ferrari pitching stuff..
https://postimages.org/
What exactly do you mean with the timing of the movement? And what would the damping respond to other than simple movement?henry wrote: ↑23 Feb 2019, 12:29From the point of view of the SF90 what’s interesting is the amount of movement, suggesting soft springs, and the timing of the movement which suggests the “damping” is responding to something other than just simple movement. People in earlier posts have suggested some possible theories on this.Cedo wrote: ↑23 Feb 2019, 01:16Here is Marc Priestley explaination to someone asking him what going on with the Ferrari pitching stuff..
https://postimages.org/
There is some miscommunication going on here.gandharva wrote: ↑23 Feb 2019, 11:22Are you blind? This one was used for that comparison shots that go around in the forums:
https://media.giphy.com/media/1yTgcCeZM ... source.gif
And then downwoting my post on top of it. Welcome to my ignore list.
Ferrari still moves the same DRS or not.Godius wrote: ↑23 Feb 2019, 13:10There is some miscommunication going on here.gandharva wrote: ↑23 Feb 2019, 11:22Are you blind? This one was used for that comparison shots that go around in the forums:
https://media.giphy.com/media/1yTgcCeZM ... source.gif
And then downwoting my post on top of it. Welcome to my ignore list.
He posted the Ferrari/RBR DRS comparison via a mp4 link but in a [/img] tag, it does not show up on the forum board. When you quote his comparison post you can see the actual link:
Ferrari: https://i.imgur.com/z8BkP8W.mp4
RBR: http://i.picpar.com/2zhd.gif
I mean... I *just* showed you the screenshot with the drs open in the comparison that I posted (not the ‘shots that go around the forum’ - what I posted).gandharva wrote: ↑23 Feb 2019, 11:22Are you blind? This one was used for that comparison shots that go around in the forums:
https://media.giphy.com/media/1yTgcCeZM ... source.gif
And then downwoting my post on top of it. Welcome to my ignore list.
Did you take into account the wheel radius and possible uphill or downhill movement while braking?henry wrote: ↑23 Feb 2019, 12:29The first part of thisCedo wrote: ↑23 Feb 2019, 01:16Here is Marc Priestley explaination to someone asking him what going on with the Ferrari pitching stuff..
https://postimages.org/
“The Ferrari more softly sprung to encourage weight transfer”
Is wrong on two counts.
Firstly the “transfer” of tyre load from front to rear is not dependant on the suspension stiffness. They could run no suspension at all and the exact same change would happen. What the stiffness does is affect the amount of movement and how quickly that movement happens. The first is down to the springs and the second the damping elements. So a car with soft suspension moves more in response to the exact same forces experienced by a more stiffly sprung car.
Secondly it’s not “weight” that gets transferred it’s load. Load is the sum of the downward forces acting on the axles. The weight of a car is one of those forces. It is the mass of the car being accelerated downwards by gravity.
From the point of view of the SF90 what’s interesting is the amount of movement, suggesting soft springs, and the timing of the movement which suggests the “damping” is responding to something other than just simple movement. People in earlier posts have suggested some possible theories on this.
One effect of holding the car down at the beginning of braking in this way would be to reduce the load transfer by keeping the centre of gravity down, essentially making the car perform as low rake before transitioning to high rake just before corner entry. I don’t know why this would help.
Here’s an explanation of my understanding. The forces on the axles get redistributed by simple physics.
When the car brakes a rearward force is generated at the tyre/road surface boundary. This is matched by a force acting through the CoG. This pair of forces tries to tip the car forward and is resisted by an increase in force on the front axle and an equal reduction in force on the rear axle (the load transfer). The magnitude of the load transfer is determined by the ratio of the height of the CoG above the road surface to the wheelbase.
For a car mass 800 kg, CoG height 36cm, wheelbase 360cm, braking at 4g. The braking force is 32000N and the force transfer 3200N. Which is 320kgf or 700lbf.
By timing I mean how fast or slow the suspension movement is, and in the case of the SF90 how it is displaced in time from the initiating event.LM10 wrote: ↑23 Feb 2019, 13:04What exactly do you mean with the timing of the movement? And what would the damping respond to other than simple movement?henry wrote: ↑23 Feb 2019, 12:29From the point of view of the SF90 what’s interesting is the amount of movement, suggesting soft springs, and the timing of the movement which suggests the “damping” is responding to something other than just simple movement. People in earlier posts have suggested some possible theories on this.Cedo wrote: ↑23 Feb 2019, 01:16Here is Marc Priestley explaination to someone asking him what going on with the Ferrari pitching stuff..
https://postimages.org/
In the simple case of load transfer under braking I don’t think wheel radius or slope has a part to play. The forces involved are either parallel to the road surface or perpendicular to it.JondoIramat wrote: ↑23 Feb 2019, 14:31Did you take into account the wheel radius and possible uphill or downhill movement while braking?henry wrote: ↑23 Feb 2019, 12:29The first part of thisCedo wrote: ↑23 Feb 2019, 01:16Here is Marc Priestley explaination to someone asking him what going on with the Ferrari pitching stuff..
https://postimages.org/
“The Ferrari more softly sprung to encourage weight transfer”
Is wrong on two counts.
Firstly the “transfer” of tyre load from front to rear is not dependant on the suspension stiffness. They could run no suspension at all and the exact same change would happen. What the stiffness does is affect the amount of movement and how quickly that movement happens. The first is down to the springs and the second the damping elements. So a car with soft suspension moves more in response to the exact same forces experienced by a more stiffly sprung car.
Secondly it’s not “weight” that gets transferred it’s load. Load is the sum of the downward forces acting on the axles. The weight of a car is one of those forces. It is the mass of the car being accelerated downwards by gravity.
From the point of view of the SF90 what’s interesting is the amount of movement, suggesting soft springs, and the timing of the movement which suggests the “damping” is responding to something other than just simple movement. People in earlier posts have suggested some possible theories on this.
One effect of holding the car down at the beginning of braking in this way would be to reduce the load transfer by keeping the centre of gravity down, essentially making the car perform as low rake before transitioning to high rake just before corner entry. I don’t know why this would help.
Here’s an explanation of my understanding. The forces on the axles get redistributed by simple physics.
When the car brakes a rearward force is generated at the tyre/road surface boundary. This is matched by a force acting through the CoG. This pair of forces tries to tip the car forward and is resisted by an increase in force on the front axle and an equal reduction in force on the rear axle (the load transfer). The magnitude of the load transfer is determined by the ratio of the height of the CoG above the road surface to the wheelbase.
For a car mass 800 kg, CoG height 36cm, wheelbase 360cm, braking at 4g. The braking force is 32000N and the force transfer 3200N. Which is 320kgf or 700lbf.