2021 Floor changes vs car rake

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raymondu999
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2021 Floor changes vs car rake

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Just wondering what you bright minds thought about this.

Surely with the floor cutouts coming in next year, cars with different rake philosophies will be affected differently. Would the higher rake floors not be affected more? Or would they in fact be benefitted more as they could somehow perhaps make downwash sidepods to help seal the diffusers with airflow coming over the sidepod? I'm no aero expert but I'm thinking something along the lines of the MP4-25's "downwash" type sidepods

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f1motta
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Re: 2021 Floor changes vs car rake

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Craig is talking about it in this video (skip to 4:33):


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jjn9128
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Re: 2021 Floor changes vs car rake

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raymondu999 wrote:
Fri Jan 22, 2021 12:07 pm
Just wondering what you bright minds thought about this.

Surely with the floor cutouts coming in next year, cars with different rake philosophies will be affected differently. Would the higher rake floors not be affected more? Or would they in fact be benefitted more as they could somehow perhaps make downwash sidepods to help seal the diffusers with airflow coming over the sidepod? I'm no aero expert but I'm thinking something along the lines of the MP4-25's "downwash" type sidepods

https://upload.wikimedia.org/wikipedia/ ... _Jerez.jpg
High rake vs low won't make much difference. It'll affect both similarly. Those floor edge slots are about keeping tyre squirt out of the diffuser which is an issue regardless of how high the rear axle is.

As for a "coanda" side pod, teams wouldn't want to give away the undercut space. Also the main mechanism was the deflection of the exhaust plume so not much benefit.
#aerogandalf
"There is one big friend. It is downforce. And once you have this it’s a big mate and it’s helping a lot." Robert Kubica

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JordanMugen
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Re: 2021 Floor changes vs car rake

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jjn9128 wrote:
Fri Jan 22, 2021 1:46 pm
High rake vs low won't make much difference. It'll affect both similarly. Those floor edge slots are about keeping tyre squirt out of the diffuser which is an issue regardless of how high the rear axle is.
Good to hear. =D> =D>

Shall we assume then that Mr. Szafnauer is merely stirring the pot and being deliberately provocative without any basis? :?: :) Trying to blame the regulations for Aston Martin Racing doing a "bad" job? :)

Otmar Szafnauer:
When we last raced here in Bahrain – just four months ago – we were heading for a podium, on merit, before a power unit issue ended Checo's race. We will not be anywhere near that kind of performance here now, and the direct cause of that performance drop-off is the new-for-2021 aero regulations, imposed on all the teams.

If you compare the qualifying times between those two races here in Bahrain, now and four months ago, it looks like the high-rake aero philosophy cars have gained around a second per lap compared to the low-rake aero philosophy cars.

So Mercedes and ourselves are the teams worst affected.

I'm not happy, and when I say I'm not happy, I mean I'm not happy for our two great drivers; I'm not happy for the 500 great men and women who designed, built and are now running our new car; and I'm not happy for our sponsor-partners or our fans, either.

After carefully analysing data from testing and this weekend, it is clear that the new-for-2021 aero regulations have impacted cars with a low-rake aero philosophy significantly more damagingly than cars with a high-rake aero philosophy. Specifically, the change in floor dimensions and profile at the rear of the cars has had a profound negative effect on the performance of cars with low-rake aero philosophy, such as our car and the Mercedes car.

It is not only us who are speaking about this issue – Toto spoke about it in the FIA press conference yesterday.
We cannot make a change to a high-rake aero philosophy car even if we wanted to, and neither can Mercedes, because the suspension on this year's cars has been homologated.

What I'm saying is that the new-for-2021 aero regulations have impacted cars with a low-rake aero philosophy more damagingly than cars with a high-rake aero philosophy. So Mercedes and ourselves have suffered, whereas the high-rake aero philosophy cars such as those of Red Bull and Alpha Tauri, and McLaren and Ferrari, have not.
https://www.motorsport.com/f1/news/new- ... n/5941007/

I thought such pot-stirring was usually the domain of Dr. Marko or Mr. Tost! :lol: For Mr. Szafnauer to blame, without any basis, the regulations changes as targeting the Mercedes and Aston Martin cars seem outrageous! :shock:

Edit: Bizarrely, Hamilton is also stirring the pot with a similar theory.

Lewis Hamilton:
It's no secret that what the changes [have done], of course they've been done to peg us back."
https://www.motorsport.com/f1/news/hami ... 40/?nrt=54

Surely these allegations of FIA bias are entirely unfounded!?

bonjon1979
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Re: 2021 Floor changes vs car rake

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Plus ca change. When red bull dominated, wing deflection tests were increased, blown diffusers banned, hot blowing etc. I’m a Mercedes and Hamilton fan, but this is the way it is and has always been. I also welcome it, red bull are clearly ahead at the moment but who knows what will happen at other tracks and development. Excited to see a challenge, do feel a bit sorry for Aston Martin but not that sorry...

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jjn9128
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Re: 2021 Floor changes vs car rake

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JordanMugen wrote:
Sat Mar 27, 2021 7:33 pm
Edit: Bizarrely, Hamilton is also stirring the pot with a similar theory.

Lewis Hamilton:
It's no secret that what the changes [have done], of course they've been done to peg us back."
https://www.motorsport.com/f1/news/hami ... 40/?nrt=54

Surely these allegations of FIA bias are entirely unfounded!?
Hamilton has a perpetual victim complex - it seems to be what drives him on - the narrative of him vs the world. I wouldn't put it past Motorsport.com not to snip a quote out of context though. The changes were obviously done because with the same rules the Pirellis wouldn't hold up. Nothing like 2005 where the FIA were overtly out to stop the Ferrari dominance.

Not sure why high rake would have been less affected but it does seem that Merc/Aston have had a worse winter - perhaps less to do with the outer edge cutouts and more the diffuser strakes to ground interaction?!
#aerogandalf
"There is one big friend. It is downforce. And once you have this it’s a big mate and it’s helping a lot." Robert Kubica

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MtthsMlw
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Re: 2021 Floor changes vs car rake

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jjn9128 wrote:
Sat Mar 27, 2021 9:30 pm
Hamilton has a perpetual victim complex - it seems to be what drives him on - the narrative of him vs the world. I wouldn't put it past Motorsport.com not to snip a quote out of context though. The changes were obviously done because with the same rules the Pirellis wouldn't hold up. Nothing like 2005 where the FIA were overtly out to stop the Ferrari dominance.

Not sure why high rake would have been less affected but it does seem that Merc/Aston have had a worse winter - perhaps less to do with the outer edge cutouts and more the diffuser strakes to ground interaction?!
Uneducated guess but maybe the lower rake (less diffuser volume) cars need more help from the strakes to expand the air out. Now they have been clipped and are less effective.

Jolle
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Re: 2021 Floor changes vs car rake

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That Mercedes thinks that the rules were changed in a way that they would suffer the most isn’t that strange. FRIC, cutting down of the amount of oil used during a race, engine modes and DAS were all changed because they thought Merc had an advantage in that area. The only other big change was adding a second fuel flow meter that had nothing to do with them.

TimW
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Re: 2021 Floor changes vs car rake

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Otmar simply pays the price for copying. If you have a car that you do not fully understand, and then have a rule change, sure you will be caught out.

Mercedes was still the fastest car on mediums yesterday, despite stability issues. Without one single driver they would have locked out the front row. In a car with some issues to solve..... I would not bet my money on red Bull yet.
Mercedes are simply claiming the underdog position now they can. All the more heroics and media attention when they come out victorious.

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jjn9128
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Re: 2021 Floor changes vs car rake

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MtthsMlw wrote:
Sat Mar 27, 2021 11:23 pm
jjn9128 wrote:
Sat Mar 27, 2021 9:30 pm
Hamilton has a perpetual victim complex - it seems to be what drives him on - the narrative of him vs the world. I wouldn't put it past Motorsport.com not to snip a quote out of context though. The changes were obviously done because with the same rules the Pirellis wouldn't hold up. Nothing like 2005 where the FIA were overtly out to stop the Ferrari dominance.

Not sure why high rake would have been less affected but it does seem that Merc/Aston have had a worse winter - perhaps less to do with the outer edge cutouts and more the diffuser strakes to ground interaction?!
Uneducated guess but maybe the lower rake (less diffuser volume) cars need more help from the strakes to expand the air out. Now they have been clipped and are less effective.
I'd think more that the lower rear ride height means the peak pressure is lower, so the pressure gradient is more severe, so the strakes become more important to keep the flow attached so they're stalling at an earlier point than before so the balance becomes unstable (all conjecture). I guess we're saying the same thing just wording it differently.
#aerogandalf
"There is one big friend. It is downforce. And once you have this it’s a big mate and it’s helping a lot." Robert Kubica

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raymondu999
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Re: 2021 Floor changes vs car rake

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So to my layman’s eye, albeit only after 4% of this year’s racing, it does seem that (at least on certain tracks) the low rakers definitely seem to have lost more than the high rakers here.

Thoughts?
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