Blown Diffuser??

[wesley123]

Well if i'm correct such gearboxes are forbidden, so that is not an option

[speedsense]

Speedsense - The maps are programmed in the SECU in the garage. A change of ignition map can only be selected when stationary. A change of throttle map can be changed at any time.

Yes, but only the rate of the throttle can be changed (in mapping), not the calibration. In other words you can't "artificially" change the throttle position (it's calibration) per the throttle pedal location. When the throttle is off, the throttle opening must also be 0%. The "delay" of lifting off the throttle and the throttle plate going to 0%, is the only element that can change. One could slow this rate down, but we are talking a long time here of off throttle (braking) and turn in, and to the apex. This is the only "artificial" throttle opening that can occur.

FIA regs- Transient throttle position compensation
Applied if the throttle demand is from the pedal. Derived from throttle position and filtered rate-of-change of throttle position.

So there could be a Q3 retarded ignition map that provides hot exhaust gas at low revs. It is selected during the Q3 pits stop. It can't run for the whole race because it would destroy the engine/exhaust.

The car doesn't need to stop to do this, can be selected while moving. Meaning the driver can "switch" to it.
So to get the desired effect, the slower throttle map inserted, dwell time voltage/time map inserted either by the driver on his "hot lap" or by writing arguments into the ECU software, and starting when all conditions (you can have many conditions or controls in the arugment for program insertion of ECU duties) are met.

2.4.6 Team Configuration
Base spark maps, dwell time voltage/time map, minimum/maximum spark advance value clipping.

As for throttle maps - Yes, the rules say that 0% throttle must equal nominal idle. However, WB's idea is for 1% throttle to give high exhaust flow but low power, ie a very fast idle with lean mix. As long as the driver doesn't take his foot off the pedal, then gasses keep flowing.

This can only be done by the driver, not through throttle maps or "artificially" changing the location of the throttle plates. Though the rate can change, leaving the throttle open long enough to "create" the desired effect that's being discussed here. That is possible.
Having a driver hold a throttle at 1% while driving a car at speed? This would be almost, if not impossible, to duplicate. He'd be lucky to stay within 15%. 1-3% throttle movement at the pedal that is near "off" could be achieved by simply moving your toes and flexing the muscles in your foot or hitting a bump.

[speedsense]

@ speedsense,

Hi speedsense,

Look I do not know, what they are doing or what they are not doing - it´s just a guess.

As for the "fooling the ECU" thought. I don`t know, what you drive as a road car, and what
other road car manufacturers doing at the moment. But, a couple of years ago, I nearly run
my car (Audi with DBW) off the road in the winter, while trying to left foot brake in a corner.

Don't have any experience with street ECU's, all of my experience is with programming racing ECU's...

Why??
Because as soon as I touched the brake, the ECU would "override" my throttle request, and stoped injecting fuel. At the time I was not expecting it, I thought the ECU would just follow my request, for some power from the engine, as I was applying throttle.
But it did not - it "decided" that I wanted to brake and "ignored" my throttle/power request.

Not related to this thread, but more than likely the brake switch is sending a on/off signal to the ecu, find that wire and cut it. Should stop the problem Also it was Audi that was first with the unintended acceleration problem, so it makes sense that this is in the car, probably as an anti-lawyer device....funny how Toyota's ECU are now showing that the drivers of most of these cars, never touched the brake but infact held the throttle open.

BTW:
In most modern road cars this is done to safe fuel under braking, as left foot braking is not considered a "normal" way to drive a road car.

...or keep the lawyers from suing for unintended acceleration when somebodies foot is on the brake...real hard to acceleration when there's no fuel..

What I want to say?
That one condition (in this case braking) can be used to "tell" the ECU that we are not in a normal x% throttle application, and the ECU would not try to apply a standard x% throttle map. Therefore it would have no influence on normal engine operation.

Writing arguments and condition programming is an art form in racing. It is a creative process and has a very broad canvass to paint. But only if the sensors and switches connected and communicating are functioning/calibrated as they are supposed to be. Otherwise, chaos follows as does the expense of a motor with a hole in it.
IMHO

[747heavy]

Hi speedsense

What is your definition of throttle calibration?
What is your definition of a throttle map?

I think we need to establish this, so that we are all on the same page.

Thanks

[F1_eng]

This is getting out of hand.

You can and are allowed to change engine calibration maps whilst the car is moving, it's done many many times a race by each driver, been done for years.

There are some crazy ideas suggested, whatever is decided, the methods used under braking must be less exhaustive to the driver than controlling the car would otherwise be. By this I mean, you don't want the driver to have to find 1% throttle opening during heavy braking or any other idea for this concept to work, he could simply put the same effort in to keeping the car under control with it being a little more sensetive to throttle.

I don't think as a whole, people have an understanding of the timings and what is going on in the cylinder with retarded ignition. One of you should come up with your proposed view for the cylce to be clarified or the end goal and effects will be completely different.

The reason an Audi will shut fuel during torque demand and braking is a safety issue, the only direct method of engine speed control is through the ECU. If a faul of some of these circuits such as the injector driver was to be permanently earthed for whatever reason, that injector would inject continuously without control. The engine and the car could be out of control, but with this system, if the driver touches the brake pedal, the injectors lose any ability to inject. Nice simple, safe system. Ofcourse it could be done with other methods such as breaking down the combustion completely with exhaust gases via the EGR circuit, which is not quite as quick.

[autogyro]

Hi autogyro,

Yeap see your point.
In theory the best solution for a EBD car would be to run an CVT gearbox, so you can
keep the engine at it´s optimum operation point.
Not sure if the sound of such a car would be very appealing for the general public.

As an crude way to do this now, you could simply clutch, and let the engine at max rpm (the rev limiter takes car of the rest), to maintain full exhaust flow.
Just kidding......

I will try again.
Control over components used for the KERS system is free, including the throttle.
If the KERS system is on the gearbox and not the engine, then the engine can be completely diconnected from the gearbox under braking. The KERS system on the gearbox then recovers energy and by being controlled in this process it replaces the engine in supplying the controlled over run braking needed by the driver for control. At the same time the engine is free to be throttled to supply a controlled exhaust gas volume for the diffuser.
If an exhaust gas fluidic switch can also be developed similar to the one used on the f-ducts on clean air. It could be used to divert the exhaust flow away from the diffuser when the car was at high speed and on the strait.

[747heavy]

Hi autogyro

Was there not a gentleman agreement in place that nobody would use KERS this year?
I see your reasoning autogyro, but I think it´s overkill for what they want to achieve.
I´m not argueing against the technical possibility of your idea.

[747heavy]

Writing arguments and condition programming is an art form in racing. It is a creative process and has a very broad canvass to paint. But only if the sensors and switches connected and communicating are functioning/calibrated as they are supposed to be. Otherwise, chaos follows as does the expense of a motor with a hole in it.
IMHO

Not arguing against this, just wanted to say/show that you can use additional imputs/arguments to override values from your correctly calibrated sensors, and create a new condition, whithout the need to compromising your calibration, and
affecting ozher conditions.

AFAIK - F1 (as most modern road cars) uses a torque controller, so their are many additional variables in play, then just throttle position to define torque/power output of the engine.

[WhiteBlue]

IMO autogyro is talking about the beneficial effects of using alternative systems to todays regulations. This is something that isn't helpful for understanding the regulations as they are at the moment. It is confusing the issue. He should open a thread about future regulation proposals to discuss this. The blown diffusor issue should be based on 2010 regulations, IMO.

[speedsense]

Hi speedsense

What is your definition of throttle calibration?
What is your definition of a throttle map?

I think we need to establish this, so that we are all on the same page.

Thanks

When you hook up a throttle sensor (or any sensor for that matter) you must calibrate that sensor so the ECU can understand what the range of 0-5,12,16 volts means. This calibration process, is either linear (two points of reference, with thottle that would be 0,100% or nonlinear with multiple points through the range (for instance a table of values for increments of the voltage output of the sensor, for example- Temp sensors are setup this way)

A throttle map, according to the FIA's rules is a mapping of the rate, or rather a "filtering" of the rate, the delay between the throttle pedal and the throttle plate and how fast that occurs. It can only be a delay..
For instance, first gear may have more delay, allowing a "less" sensitive throttle pedal, 7th gear may have zero delay, as it's less likely to create wheelspin with agressive throttle input. It is only the response time you are effecting. This would be the intent of the "mapping of the throttle". (If this were a mechanical cable device, the ratio of the opening of the butterfly vs. the throttle would be altered by leverage. Similar effect, but not the same in this instance).
Though using it to keep the throttle open, in off throttle situation, by delay, say in 6th or 7th gear, would be an "artful" approach...
Effectively, mapping of the throttle, is changing the timing between the driver's input and the throttle plate response rate.

[autogyro]

A bit like altering the angular geometry on a conventional throttle cable operated carb or induction butterfly.
I cannot see much benefit in doing this, other than for fine tuning driveability.

IMO most of the mapping for improved EBD gas flow works on the ignition advance/retard and the injectors.

[747heavy]

Thanks speedsense for the explainantion.
I agree with what you say.
So can we conclude, that for the function of the engine, the value of the throttle plate at the engine is taken and that the value of this is carefully calibrated?

If we can, then the position of the throttle plate is the primary function.

The position of the pedal can be indepentend of that.
The throttle map defines the relation between the position of the throttle and the position of the throttle plate at the engine.
Where, by the rules, 0% pedal has to correlate with 0% at the engine (or the idle setting) and 100% pedal has to correlate with full throttle.
In between the relation does not need to be linear.

Now, we would need to define (or know the rules) how many dimensions(additional inputs) a throttle map can have, and if the throttle operation has to be symetric
for going from 0-100% and coming from 100%-0%.

@autogyro
I agree with you last statement.

And as I said, to my knowledge, F1 operates a torque controller, so response from the engine to let´s say 60% throttle will depend, from many other parameters (e.g. rpm, gear, air temp etc.), not just the 60% throttle position signal.

[WhiteBlue]

I'm pretty sure there are multiple input and output parameters to engine maps.

Inputs may include: Throttle actuator signal, ion current signal, selected gear, launch or race selection switch

Outputs may include: Throttle plate angle, ignition timing, fuel injector timing

The SECU program is likely to take care of the input variation while the different maps contain the three dimensional output variables.

[speedsense]

A bit like altering the angular geometry on a conventional throttle cable operated carb or induction butterfly.

With very high horsepower, problems exist with wheelspin and driver sensitivity to the throttle. An F1 car in first or second gear and zero delay could be almost impossible for a driver to have enough sensitivity in his right foot to control it. Imagine the tires wearing out and the potential for wheel spin increase on the same throttle zero setting AND a lightening fuel load at the same time, adding more acceleration with less rear grip.
At some point the throttle pedal becomes impossible for the driver to be sensitive enough.

I cannot see much benefit in doing this, other than for fine tuning driveability.

It was mentioned in the thread that having the throttle plates open by a low percentage while at off throttle, retarding the timing would have the effect described by Scarbs. Setting a "long" delay would achieve the slightly open throttle effect.
In high horsepower cars, it's not only the throttle throw that is changed, but also the car can be geared higher for 1st,2nd,3rd so that the peak torque curve of that corner and where the driver hits full throttle are delayed slightly, moderately or a lot (like a hairpin)... for instance, when the driver gets to full throttle, the gearing puts him below the optimum torque (for that corner) and acts like an artifical traction control.
In F1, the throttle map achieves this and allows a lot of flexibility for the types of corners and allows the car to be geared much closer to max torque, if not dead on it. IMHO

IMO most of the mapping for improved EBD gas flow works on the ignition advance/retard and the injectors.

IMO as well, especially the delay aspect of the throttle closing makes it very possible.
Red Bull's "advantage" with the EBD, seems to be in the high speed corners, and some in the med-high speed corners. These corners would have much less braking or just a lift. Flat out wouldn't need the map. And with putting a delay in the higher gears for these corners to help achieve the EBD effect, with the dwell timing retard map automatically put in by the ECU. The mapping in the ECU can include enough sensors for the arguments/conditions, that the location on the track and the installation of the retard map can coincide. The driver would switch to this condition at the beginning the lap, and the ECU could take over from there.
Because of the damaging effect to engine, they may only be using it in a few corners and as little as needed.
Further more, it is possible it could be used during the race as well, for passing or preventing a pass. Only RB would knows how many times they can get away with it. IMHO

[autogyro]

I doubt the other teams will be able to make full use of the EBD before the end of the season.
There is little track test time to fine tune the drivability.
RB should hold onto the advantage.
If they do not take both titles it will be driver related.
Mind you McLaren have surprized me with their rapid improvment.