How much change of weight distribution in F1 cars?

[davidgonzalez]

Hi, as far as i know a F1 car has around 50-100 Kgs of ballast to distribute.
The lighter you can construct your chassis, the better, as you will have more ballast to play around.

My question is:

Supposing i have 75 kgs of ballast and a certain default weight distribution, how much am i able to change that?

If i have a front:rear distribution of 43%:57%, how much would i be able to change it?

[pRo]

If i have a front:rear distribution of 43%:57%, how much would i be able to change it?

Say you have that with 500kg car and you have 100kg ballast.

You'd have 215kg(43%) on the front and 285kg(57%) on the rear.

215+100:285 would be 52.5%:47,5% (from a total of 600kg)

215:285+100 would be 35,8%:64,2% (from a total of 600kg)


In theory, you could place the ballast in front of the front axel, which would actually lighten the rear axel a bit, but that would make no sense.

[davidgonzalez]

I dont think its as easy as you say, keep in mind you cannot place all the weight on the nose of the car.

I would like some engineer or someone related with F1 to answer if he knows this.

[pRo]

I dont think its as easy as you say, keep in mind you cannot place all the weight on the nose of the car.

I would like some engineer or someone related with F1 to answer if he knows this.

I think you got me wrong, I was trying to say you could change it more than you ever wanted to. Or maybe I got you wrong? I thought you asked how much you could change that? If it made the car faster on one track, I'm sure every team would find a way to place the ballast on the front axel.


In reality, you'd never need to change it that much. I've done some racing (not with F1) and we only change the distribution less than 3% from track to track.

[davidgonzalez]

Well, im asking cause ive read a lot about the subject but cannot find anything.

For example we often read about how renault 2003 season had a lot of rearbiased weight, which meant car was more oversteery, more traction onr rear wheels, and gave it a better start, but lacked in other areas cause of that rear-biased weight.

If teams would be able to shift their % of weight so much, then we wouldnt be talking about renault 2003 was so or so, or this car was more forwarded in weight distribution.

So my guess is that moving those aproximately 70 kgs the better teams may have, you can only change the % so much, and i want to know how much can they do it

[Ciro Pabón]

David, most of the over-under steer is caused by dynamic forces, that is, acceleration and deceleration. Ballast influences on behaviour of the car, but let's say it's influence is minor. Suspension tuning is much more important. You could read this famous introduction, to "get a grip" on the subject:

The physics of racing

[davidgonzalez]

Thanks mate, im not trying to understand the handling of car or how it transferr forces and weights dynamically, i just want to know how much current F1 teams are able to change the % of weight they have as "base" weight distribution

[pRo]

For example we often read about how renault 2003 season had a lot of rearbiased weight, which meant car was more oversteery, more traction onr rear wheels, and gave it a better start, but lacked in other areas cause of that rear-biased weight.

If teams would be able to shift their % of weight so much, then we wouldnt be talking about renault 2003 was so or so, or this car was more forwarded in weight distribution.

I don't think it's that simple. Some cars do good at one distribution, while the other needs something else. I'm sure the Renault had the best distribution for that car and it would've only gone for the worse, if they had changed it.

[davidgonzalez]

Hehe, i think both of you are trying to help, which i thank you for, but i just used Renault as an example that i think weight distribution can only be changed a little by placing ballasts.

So, what i want to know is how much can it be changed? i mean in %. For example if you have a F1 car with weight distribution of 43%-57% (Front-rear), by placing ballast, what is the % range you can set it to?

[pRo]

So, what i want to know is how much can it be changed? i mean in %. For example if you have a F1 car with weight distribution of 43%-57% (Front-rear), by placing ballast, what is the % range you can set it to?

I don't think you'll find a definite answer to that one. I bet teams will keep detailed info like that to themselves. I'm also sure it varies from car to car, some might change theirs more than others.


But I'm also sure that if a team found out their car would perform best at 30:70 weight distribution, that they would make it happen.

[scarbs]

Teams struggle to find places to put ballast. My understanding is that nowadays there isn’t as much ballast as there used to be, certainly 80-100kg in not likely nowadays. This is because certain parts are now made heavier such as the gear case, engine sump and chassis bottom. The option to put weight forwards is really down to how much space they can find to put the tungsten. Already the t-tray (or front floor splitter) is solid metal and the sides of the monocoque along the step are bevelled and filled with quadrant shaped lengths of tungsten. There is a FIA limit on ballast allowed in the front wing\nose cone and any where else tends to be too high. Jaguar\RedBull used to put some ballast on the single keel, this is higher than desired but was their only option.
This leaves little option to move weight forwards, I would say teams design their car for a maximum ballasted forward weight distribution and then take front ballast away when not needed. Of course teams that have underestimated the amount of forward weight bias are then stuck with few options to add it. I would say that the teams are probably not able to move the bias forwards even as much as 1% from their designed maximum.

The T tray is at least 330mm from the front axle line, putting 1% of the cars weight (6.1Kg) as ballast at that point, would yield but a 0.4% forward bias. In fact to move weight forwards by 1% you have to add as much as 17Kg of ballast right on the tip of the t-tray, this would be a strip of tungsten across the splitter (400mm) , one inch thick (25.4mm) and 85mm wide, that’s quite a big lump of ballast and comparable only to that seen on the front of the Renault floor on occasions.


Scarbs

[davidgonzalez]

Thanks a lot, your stimation on 1% change is based on any information you may know or just pure speculation? If anyone wants to keep helping, i dont want to know the exact amount, but something aproximate.

Thanks

[scarbs]

I did the calculations based on simple lever theory and dimensions I know to be accurate....

[scarbs]

Just to add an F1 team near the back of the grid currently runs 19Kg of movable ballast. There appears to be space for a little more, may be 13Kg in total in the front wing and other spare chassis compartments. But this ballast is not as far forward as in my calculations above, so has a lesser effect.

[Belatti]

... For example we often read about how renault 2003 season had a lot of rearbiased weight, which meant car was more oversteery, more traction onr rear wheels, and gave it a better start, but lacked in other areas cause of that rear-biased weight.

If teams would be able to shift their % of weight so much, then we wouldnt be talking about renault 2003 was so or so, or this car was more forwarded in weight distribution.

So my guess is that moving those aproximately 70 kgs the better teams may have, you can only change the % so much, and i want to know how much can they do it

What about conecting a Tungsten piece in the bottom of the car with a pneumatic/hidraulic (this would be feeded by the valve train feeder tank) micro-ciyinder + spring and with some kind of guidance in order to make "manettino" regulations, so that you can have rear biased weight for a better start and low speed corners traction and a better distributed weight for other parts of the track?

Now I look foward to read posts from the FIA technical regulations experts we have got in the forum

I did not read them jejej