F1 cars inability to follow: Accidental or Deliberate?

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WhiteBlue
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Re: F1 cars inability to follow: Accidental or Deliberate?

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well, perhaps the G figures should not as radically cut as I put it. I just mean that a rebalance should be found making time in slow corners and taking it from the faster. I understand that is what the 2009 rules will do anyway.

some have suggested wider tyres but I think that this would increase drag.

thinking about safety is always sensible and the size of safe run offs has been a concern for many years. that went hand in hand with ever higher G-forces. the Gs reached in the tyre war were truely excessive.
Formula One's fundamental ethos is about success coming to those with the most ingenious engineering and best .............................. organization, not to those with the biggest budget. (Dave Richards)

Scotracer
Scotracer
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Re: F1 cars inability to follow: Accidental or Deliberate?

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I think 4G is a good limit. If we can get 2.5G+ from tyres alone next year, we can easily get to 4G with the new aero regulations. This is a good level as most of the awe of an F1 car comes from the cornering speeds.

What I don't like about current cars is that they don't look like they have much power. The power they do have does not overwhelm the tyres or aero by any great margin (except at really low speeds) and the cars just seem to be on rails all the time. This makes the spectacle less. I fear this is only going to be exaggerated next year when tyre grip is increased twofold.

I feel the problem lies in the engines themselves. Whilst they have a good amount of peak power (750-800BHP), they really lack torque so they are normally within the constraints of the tyre's grip levels. We need a torque increase, not a power increase. KERS will help with this but it is not at available at all times. Even the V10s had more grip than power but it was a much better spectacle. I want to see the drivers fighting the power more! These things are some of the most powerful circuit racing cars in the world (well, they are pretty much #1) yet they look as docile as an F3 car. :|

What I feel would be a possible solution is to do what the FIA did with WRC - limit peak BHP but allow torque curve optimisation. Say they limit to 850BHP @ 19,000rpm power limit (a great figure for both performance and awe) but still allow engine development, we could see much, much better torque figures making the cars a handful.

Well, one can dream :D
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Ogami musashi
Ogami musashi
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Re: F1 cars inability to follow: Accidental or Deliberate?

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To me G's are not a problem. It is misleading to read G's measures like that.

As i said a 80km/h corner can be as high as 3g's yet this is not a high speed corner, it all depends on the radius of the turn.

I think F1 cars are about high speed turning so, without going into extremes, 5G+ is good measure with a comfortable margin before some other cars can go that fast into the same corners.

What is more important is the grip curve.

I bet next year this will be a bit interesting as with speed the grip will go more and more down compared to now.

I'm not quite sure the cars will be slower in high speed corners.

I did some calculations and found that with 2,5 of maximum tyre friction coefficient it only require the weight of the car in downforce to have 5g's.

of course a tyre friction coefficient is not constant, but i think we could see cars going about the same speed, which would mean faster lap times considering the low to medium speed corners.

I think what is important is to have a lot of grip for racing. If your car has not so much grip then your racing lines decrease.

So i think this is good that cars have a lot of grip.

It is kind of striking that in the recent years, only F1 cars slowed down.

GP2 cars are considerably faster than F3000. The new A1GP car is said to be about 9 seconds a lap faster than the current, new FN car will be into the GP2 lap times, and superleague formula car slightly above.

All those series look for a balance of thing providing good grip.


About the power of F1 cars, i don't have the feeling they are on rails, i think this is mileading, the problem is that the tyres are of the type of "sudden loss", they just "stall". So drivers keep on saying they can't drive aggressively.
When they tested slicks they expressed their please to be able to actually push the cars.

A thing confirmed by JV in his recent LMS drive were he said that slicks tyre gave the car good grip and predictability so that compared to an F1 car he could push it hard.

I think next year that'll be cool, also don't forget next year 80 more horsepower will be here and that this power will be delivered directly to the powertrain (via the gear box if i'm correct)so i think that'll give a kind of real boost!
(but i don't know too much on engines/powertrain so i may be wrong).

Scotracer
Scotracer
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Re: F1 cars inability to follow: Accidental or Deliberate?

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But surely there will be a lateral limit on the centripetal accelereation?

I had noted when reading the through the now defunk 2009 regulations on the FIA website that they stated that downforce levels should not exceed 1200kg at any point. This is 2x the car's weight in downforce so the cars, with slicks will be able to corner at tremendous speeds -- probably overall faster than today. What would be more beneficial to the cars is to significantly reduce drag. These cars produce too much so the power they do have is wasted in pushing them down the straights. I sincerely hope they have reduced drag levels next year.

I am all for a radical change, as long as the cars do not lose any pace over todays, as I feel they are too slow as it is.

As for the KERS input...will there be an overall increase in power (i.e. at all times) or will it just be when the push-to-pass is used? I had heard that around 30BHP would be added above the 750 they have now and then a further 50 would be available via the push to pass. Is that correct?
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Ogami musashi
Ogami musashi
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Re: F1 cars inability to follow: Accidental or Deliberate?

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The problem with downforce measurements is that they are just maximums and thus it applies only to straight line speeds.

An actual F1 car in monaco trim makes about 2700KG of downforce at 320km/h....but who cares? an F1 car is not able to go that fast over monaco, even less going into a corner of monaco that fast.

Also when turning the downforce decreases because the velocity field decreases+flow field over the wing change.

The tyre load sensitivity also plays a large role. In some turns it is better to have less downforce to preserve the tyre's grip or else you end up with less grip.

Similarly you need to make trade offs between the speed needed for straight line of course but also some corners and the grip you need for some slower ones.
Istanbul is a good example, the low to medium downforce wings setting are just there because you need low drag to get into Turn 8...If that turn was not there, F1 cars would run with bigger downforce settings.


So it is very hard to tell what will be at a precise moment in a corner the grip.

I think that next year, tyre's load sensitivity will be less because first of all slicks tyre are more flexible and you'll have less downforce.

I also think under turning downforce will be (proportionally) higher because the larger front wing closer to the ground and higher rear wing will surely better work so who knows??

But don't trust the maximum numbers. In 2006 we know cars could turn 8 at istanbul at 5Gs (270km/h), that makes about 650kg (i take an average weight with fuel) times 5= 3250 grip.
The tyre's max coefficient was about 2 so you had 3250=(2*650)+(2*dowforce) which made (2*downforce)=3250-(2*650)=1950 so max downforce was= 975Kg..at 270km!

If you took the calculation of monza type wings you end up at 1922,16Kg!

Scotracer
Scotracer
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Re: F1 cars inability to follow: Accidental or Deliberate?

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Thanks for clearing that up. I was a bit pre-emptive suggesting that the fluid flow wouldn't be altered by cornering.

Would a 2008 car be able to reach 320km/h using a monaco aero setup? Wouldn't the drag be insurmountable?

What are the reasons for having to use a low downforce setup for Turn 8? I would have guessed that high downforce would have been necessary (just like other tracks with fast corners, i.e. Silverstone) to be able to corner at those speeds?

It makes for an interesting discussion, nonetheless.
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Ogami musashi
Ogami musashi
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Re: F1 cars inability to follow: Accidental or Deliberate?

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I don't know if F1 cars could go to 320km/h with monza type, i think yes because there're other tracks like magny cours were they run high downforce setting and cars go near 320km/h (slightly less), all is a question of acceleration.


The reason for turn 8 is drag. When you turn you loose downforce but also increase drag by two ways mainly, two being pressure drags, the first being a pressure drag between the inner part of the wing (the part of the wing turned inside the corner) and the outer part, the next is the frontal area presented by the complete bodywork which is greater of course (because there's a sideways movement plus a rotation).
You also have crossflows that can trigger turbulence, and chassis pitch up/down that can during the turn increase the effective AOA of the wing occuring stalls.

Add to that the tyre's total grip traded from longitudinal to lateral load and cars inevitably slow down.

So, since you can't get to that speed, you're forced to go through the turn slower....except if, by getting lower drag setting, you can get to a speed providing enough grip, that's the case for turn 8 in instanbul.

In Spa, eau rouge in another example, a little bit different but interesting. Here the compression of uphill offers a positive G's load (up to 4,5G in F1) so actually works like if you add 4,5G of grip coming suddenly, so you need very few downforce.
This corner is drag limited and almost every car can take it flat out (but of course terminal speeds vary from series to series).

So as you see, the reality is far from simple radius over speed calculations as you need to take into account many things, and you also understand why set ups can be so hard to find for a track.

That's why in another posts i said the day adaptive (or mobile) aerodynamics are allowed, it will completely revolution the design of F1 cars.

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WhiteBlue
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Re: F1 cars inability to follow: Accidental or Deliberate?

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One thing is clear. In the days when Jacques destroyed two BARs in one weekend to take Eau Rouge flat cars did have less aero downforce and a lot more grip. with the actual cars you have so much downforce that mechanical grip doesn't matter at all. things have changed.
Formula One's fundamental ethos is about success coming to those with the most ingenious engineering and best .............................. organization, not to those with the biggest budget. (Dave Richards)

Scotracer
Scotracer
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Re: F1 cars inability to follow: Accidental or Deliberate?

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WhiteBlue wrote:One thing is clear. In the days when Jacques destroyed two BARs in one weekend to take Eau Rouge flat cars did have less aero downforce and a lot more grip. with the actual cars you have so much downforce that mechanical grip doesn't matter at all. things have changed.
Hmm, that would be the year 1999? When him and Zonta stuck it in the wall? That year was the 2nd year after the track reduction and the first year of 4 grooves on the front tyres. I'm sure this would mean the cars had less mechanical grip than now (even though we are running control tyres, they are still pretty grippy).

Downforce levels? Well, they had a more rear-ward rear wing (bigger moment about the rear-axle therefore more downforce), more aerofoil sections on that rear-wing, a bigger diffuser and a much lower front wing. Hmm, I would say at least as efficient as today. Although, saying that the cars were on average around 8 seconds a lap slower than today...with probably a similar level of power.

I would say those crashes were caused by handling problems more than anything as it was specifically the BAR 199 that it happened too. Watching the footage, it was on turn-in where the rear of the car became unbalanced and swapped ends on him.
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WhiteBlue
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Re: F1 cars inability to follow: Accidental or Deliberate?

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Scotracer wrote: ...
Downforce levels? Well, they had a more rear-ward rear wing (bigger moment about the rear-axle therefore more downforce), more aerofoil sections on that rear-wing, a bigger diffuser and a much lower front wing. Hmm, I would say at least as efficient as today. Although, saying that the cars were on average around 8 seconds a lap slower than today...with probably a similar level of power.
1. whenever will people recognise that aero efficiency isn't about the level of downforce but about drag. in road car design it is called cw

2. considering they ran similar tyres and power it most likely was the different downforce. its the things you dont see like floor design, and flip ups, winglets and all these bits and bobs they have today
Formula One's fundamental ethos is about success coming to those with the most ingenious engineering and best .............................. organization, not to those with the biggest budget. (Dave Richards)

Ogami musashi
Ogami musashi
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Re: F1 cars inability to follow: Accidental or Deliberate?

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the peak of downforce in history of f1 was reached in 2004.
it was about 3 tons max at 320km/h.

The downforce was reduced in 2005 then again reduced in 2006, however in 2006 the tyre war was at his best (or worst depending on your view) and tyres offered incredible grip (considering they were grooved) so except in corners drag limited and slow speed acceleration 2006 cars had more grip.

however most of the records are held by F2004 and MP4/21 from 2005.

the downforce levels in 99 were not so high, at 300km/h on a medium trim one could except 1800Kg. The downforce levels grew from 2000 to 2004 steadily to reach that enormous peak in 2004.

mechanical grip matters in the way that when you apply a load on the tyre, the grip of the tyre decreases (that's why with same chassis, suspension and tyre, an heavier car will have less grip), so too much downforce is not good.

The thing in 2009 is that the curve of downforce will be flatter because the total grip will be far higher than in the mid 90's and a huge part of that grip comes from the tyres, so high speed cornering will have a limit anyway but i'm almost sure most of the high speed corners (250km/h and more) will be taken at the same speed, and drag limited ones will be maybe taken even higher with KERS.

That's interesting anyway to change the grip curves sometimes.