Asymmetric suspension setup in F1?

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peanutaxis
peanutaxis
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Joined: 23 Jun 2012, 11:32

Re: Asymmetric suspension setup in F1?

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I'm pretty sure that they'd run symmetric suspension. But I'm sure I've seem asymmetric front wings before.

xpensive
xpensive
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Re: Asymmetric suspension setup in F1?

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Jersey Tom wrote: ...
NASCAR setups have more asymmetry than you can shake a stick at. Things that you wouldn't even think COULD be asymmetric, are asymmetric.
Indeed, I remember reading somewhere that some of the most successful drivers were asymmetric as well.

But anyway, JV was known to have brought a CART-style corner-for-corner set-up to Williams in 1996.
"I spent most of my money on wine and women...I wasted the rest"

Belatti
Belatti
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Joined: 10 Jul 2007, 21:48
Location: Argentina

Re: Asymmetric suspension setup in F1?

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I remember using a pretty asymetric setup here:

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"You need great passion, because everything you do with great pleasure, you do well." -Juan Manuel Fangio

"I have no idols. I admire work, dedication and competence." -Ayrton Senna

gixxer_drew
gixxer_drew
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Re: Asymmetric suspension setup in F1?

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Wait DaveW so you are saying there are people who don't use asymmetric setups at least from time to time? That was one of the top tools in my box. Good example would be Infineon (Yes, I grew up in the states). Every right hander is low speed every left is higher speed. Holding to symmetry seemed like it would just leave something on the table. Not that I would ever dare go toe to toe with you in a vehicle dynamics discussion, I'm just curious?

Jersey Tom
Jersey Tom
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Re: Asymmetric suspension setup in F1?

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gixxer_drew wrote:Holding to symmetry seemed like it would just leave something on the table.
As a race engineer, you are always going to leave things on the table. That's a reality of life. Once that's accepted, the logical thing is to sort out what are the things to chase that are going to give you the most gain.

Maybe dicking around with some asymmetric setup option is the hot ticket at a given track. Maybe you'd be better off putting that aside and working on more conventional, symmetric setup choices.

Could make the argument.. why focus on something that just makes you turn better to the right at expense of left, when you can make changes to improve both left AND right handers.
Grip is a four letter word. All opinions are my own and not those of current or previous employers.

gixxer_drew
gixxer_drew
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Joined: 31 Jul 2010, 18:17
Location: Yokohama, Japan

Re: Asymmetric suspension setup in F1?

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Jersey Tom wrote:
gixxer_drew wrote:Holding to symmetry seemed like it would just leave something on the table.
As a race engineer, you are always going to leave things on the table. That's a reality of life. Once that's accepted, the logical thing is to sort out what are the things to chase that are going to give you the most gain.

Maybe dicking around with some asymmetric setup option is the hot ticket at a given track. Maybe you'd be better off putting that aside and working on more conventional, symmetric setup choices.

Could make the argument.. why focus on something that just makes you turn better to the right at expense of left, when you can make changes to improve both left AND right handers.
just to be clear I'm not saying i like to run non symmetrical or that I dont prefer to have it symmetrical. I'm just saying that everything has been on the table for me, and I have had to pull that out of the box at times. You guys are obviously way more experienced than I am and I bow to that for sure... though I'm just trying to poke at this a little so I can learn something here.

To answer the question about why be better at left than right, my reasoning was because the car can be better at left than right or because at a place like Infineon if you have a lot of downforce you can have a car that reacts in a weird way to that and you find yourself in a pinch with a car that has different behaviors in turning either way and not enough time to figure it out.

The top reason I ever ran asymmetrical (besides oval), was really that it often came down to a "whatever works" in that one test session we have left.

But I have done it intentionally, let me explain the situation details.

If you are corner balancing for offset weight, that has aero consequences. I first learned this on a pikes peak car in a full scale tunnel. It opened my eyes to doing roll sweeps. They wanted a setup for a road course, set the car low, they corner balanced it and we rolled it into the tunnel as it was run. It read almost 20% higher on one side. After scratching my head and recalibrating the load cells three times I walked out there to have a look and realized how much lower one side was than the other.

Aero wise.... Some cars can be so sensitive to ride height and roll that corner balancing can bias your forces big time to one side. I design GT cars so that front diffuser can be adjusted so that its entirety is at the rules height, but the rules flat bottom cannot be adjusted, neither can the rear diffuser. On some of the unlimited class time trials type of cars or pikes peak like I listed above. They will have more downforce than F1 but it will be non adjustable because it was produced on an extremely tight budget. So i think about the dynamic situation. If at speed that side of the car is going to get significantly lower from aero, I find myself in a non symmetrical condition anyway. Even a mid downforce like a SuperGT GT500 the effect is real and you get it in the driver feedback. 15% can be a really big value in terms of raw forces. How would you deal with that? Or would you?

Jersey Tom
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Re: Asymmetric suspension setup in F1?

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Sure. Point I'm most trying to make is you have to know where you're at. If you're truly bottomed out on all your other knobs for performance, then yes... asymmetry can potentially get you a gain. More so at some place than others. Lime Rock is still my favorite example of that!

I've just been on a kick lately that you gotta prioritize and know what's big and what's small. Sometimes it's easy to get caught up in the tiny bits and lose sight of the big ones!
Grip is a four letter word. All opinions are my own and not those of current or previous employers.

gixxer_drew
gixxer_drew
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Joined: 31 Jul 2010, 18:17
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Re: Asymmetric suspension setup in F1?

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Jersey Tom wrote:Sure. Point I'm most trying to make is you have to know where you're at. If you're truly bottomed out on all your other knobs for performance, then yes... asymmetry can potentially get you a gain. More so at some place than others. Lime Rock is still my favorite example of that!

I've just been on a kick lately that you gotta prioritize and know what's big and what's small. Sometimes it's easy to get caught up in the tiny bits and lose sight of the big ones!
That is true, I have to admit I have gotten caught up in that before.

I wouldn't go barking up that tree unless I was way into the nitty gritty on setup and had some reason to suspect the cause.

ubrben
ubrben
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Joined: 28 Feb 2009, 22:31

Re: Asymmetric suspension setup in F1?

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For me any closed circuit with no cross-over (a la Suzuka) has 360 degrees more cornering in one direction so it's logical to run some left / right camber split just about anywhere. I'd call that low hanging fruit to be honest.

Somewhere like Lime Rock is a complete no-brainer. 6 right-handers and 1 left-hander. you can easily gain by running softer RHS tyres and a lot less camber. If you go 0.1s quicker in each right-hand corner you need to loose 0.6 in the one left-hand corner to have zero net gain, and there are lots of ways of reducing that 0.6.

I'm always a little confused regarding the desire for a symmetric car. Are the corner-weights symmetric under trail braking? Is any circuit truly symmetric?

Ben

DaveW
DaveW
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Joined: 14 Apr 2009, 12:27

Re: Asymmetric suspension setup in F1?

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gixxer_drew wrote:Wait DaveW so you are saying there are people who don't use asymmetric setups at least from time to time? That was one of the top tools in my box. Good example would be Infineon (Yes, I grew up in the states). Every right hander is low speed every left is higher speed. Holding to symmetry seemed like it would just leave something on the table. Not that I would ever dare go toe to toe with you in a vehicle dynamics discussion, I'm just curious?
I think that JT has stated the arguments well.

One of my Indy car customers (i.e. no 3rd springs) used high value front springs (to control aero). This caused the vehicle to understeer (sorry, JT) with no front bar fitted. Their solution was to corner weight the car to favour the predominant corners. I worked through an alternative (symmetrical) set-up with them, reducing the front springs by around 40 percent, supporting the front corners at high speeds with bump rubbers (guessing an engagement speed), and having a stab at a front bar setting, roughly the way an over-sized GP2 might have been set. The objective was balanced handling and improved CPL control through low & medium speed corners. They struggled with their own solution during practice at the next road course race and finally moved the car up ten grid places with my untested "trial" (probably sub-optimal) set-up. JT's comments apply, I think.

By the way, I don't claim symmetry extends to the tyres.

Jersey Tom
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Re: Asymmetric suspension setup in F1?

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ubrben wrote:I'm always a little confused regarding the desire for a symmetric car. Are the corner-weights symmetric under trail braking? Is any circuit truly symmetric?
I'd make the argument that when you eliminate asymmetry as a setup option for your initial prep work, you can do a lot of development very quickly and cross a lot of things off the list. Much like I am a fan of using simple simulation tools and models to do the first 80% of the work quickly, then start chipping away at the last bits with slower and more involved methods.

If there's spare time before the event (bearing in mind I'm used to a race every 7 days with constantly changing tires, etc) and you've crossed off the big and easy stuff, then I'd start tweaking the dial on asymmetry.

Not so much a question of wanting a symmetric car in an absolute sense, as much as.. I'd work on that (the easy aspect) first to get the majority of performance and then squeeze the last bits out after.
Grip is a four letter word. All opinions are my own and not those of current or previous employers.

Belatti
Belatti
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Joined: 10 Jul 2007, 21:48
Location: Argentina

Re: Asymmetric suspension setup in F1?

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ubrben wrote:I'm always a little confused regarding the desire for a symmetric car. Are the corner-weights symmetric under trail braking? Is any circuit truly symmetric?
The thing is Ben, not every driver is capable of trailbraking and not every corner allows you to trailbrake all the way, at least when braking distances are long.

I have an anecdote of an Ex-F1 driver that is champion of various touring car series in my country. He was testing a car and he told the team to check the corner weights because there was at least 10Kg difference between the fronts. Do I need to tell what was the difference when the team checked it? When they asked the driver how did he know the corner weights where not symetrical, he replied "initial instablility under brakes".
"You need great passion, because everything you do with great pleasure, you do well." -Juan Manuel Fangio

"I have no idols. I admire work, dedication and competence." -Ayrton Senna

ubrben
ubrben
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Joined: 28 Feb 2009, 22:31

Re: Asymmetric suspension setup in F1?

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DaveW wrote:
gixxer_drew wrote:Wait DaveW so you are saying there are people who don't use asymmetric setups at least from time to time? That was one of the top tools in my box. Good example would be Infineon (Yes, I grew up in the states). Every right hander is low speed every left is higher speed. Holding to symmetry seemed like it would just leave something on the table. Not that I would ever dare go toe to toe with you in a vehicle dynamics discussion, I'm just curious?
I think that JT has stated the arguments well.

One of my Indy car customers (i.e. no 3rd springs) used high value front springs (to control aero). This caused the vehicle to understeer (sorry, JT) with no front bar fitted. Their solution was to corner weight the car to favour the predominant corners. I worked through an alternative (symmetrical) set-up with them, reducing the front springs by around 40 percent, supporting the front corners at high speeds with bump rubbers (guessing an engagement speed), and having a stab at a front bar setting, roughly the way an over-sized GP2 might have been set. The objective was balanced handling and improved CPL control through low & medium speed corners. They struggled with their own solution during practice at the next road course race and finally moved the car up ten grid places with my untested "trial" (probably sub-optimal) set-up. JT's comments apply, I think.

By the way, I don't claim symmetry extends to the tyres.
Hi Dave - that's funny. Doesn't that say more about aero-obsessed people than it does about asymmetry though?

Of course it might be chicken and egg, I've worked with one very good race team in particular who run a little bit asymmetrically at virtually every track and massively so at others... It might just be that they're so well drilled everywhere else that they'd be doing the same without the asymmetry, but I'm not convinced.

Ben

DaveW
DaveW
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Joined: 14 Apr 2009, 12:27

Re: Asymmetric suspension setup in F1?

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ubrben wrote:... that's funny. Doesn't that say more about aero-obsessed people than it does about asymmetry though
Hi Ben. You are right of course, but the culture of asymmetrical set-ups encouraged them to persist with their solution...

ubrben
ubrben
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Re: Asymmetric suspension setup in F1?

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Dave, I'm watching the NASCAR Nationwide from Road America on my DVR this evening and this thread seemed relevant.

If I was at Road America I'd want to ballast the car to the RHS to keep the left and right side loads more even in the dominant RH corners. I'd run a camber split for the same reason. The carousel can grain the LF so I'd run a harder LF tyre or a softer RF tyre depending on how hard the baseline is.

Another option would be asymmetric rear toe-in; more on the LR relative to the RR to tighten the RH corners and loosen the LH corners.

Which of those things wouldn't you do and why? I don't mean the question confrontationally, it's just that's my experience of the track.

Ben