Exhaust blown diffusers and FIA restrictions/ban

[hardingfv32]

"Quite. I was doing some reading around and I think you are on the money here. Say you could design an engine map that idled the engine but had 90% throttle (by closing cylinders, for instance) then you still comply with the law."

It go without saying that this isn't the map that you will use when you are in the pits or on pre-grid. The driver has to be able to change engine maps.

Brian

[bill shoe]

The James Allison article is the most specific public information we've had about the new engine mapping rules.

Based on public information, if the driver pushes the throttle pedal at least 1% into its travel then there is no restriction on throttle position, ignition timing, or anything else. Therefore, there is no change to blown diffusers IF the driver pushes the pedal 1%. All drivers use left foot braking which means the right foot is available for this throttle-cracking excercise during braking and turn-in.

I assume drivers and engineers are spending a lot of time practicing this technique on driving simulators at the factories. I assume teams will try it out on the cars during Friday morning practice in Valencia in advance of it becoming the new norm at the British GP.

Therefore, blown diffusers will not really be eliminated or significantly changed. The only difference is that drivers will have to do the silly keep-the-throttles-cracked thing during braking. This will be inconvenient, but if blowing the diffuser makes you faster then you really don't have a choice.

If I was strongly against blown diffusers then I would still wonder what the point of the new rules was. They seem too intentionally inept to make sense as an anti-Red-Bull plot. Therefore I assume they are a way for the FIA to remind people of its power and show that FOTA is submissive, sort of a probe into enemy lines ahead of the Concord negotiation battle.

[djos]

A certain amount of this is going to be handled by driving style changes .. trying to spend more time on throttle in corner entry, such as braking earlier and rolling thru corner entry on some throttle to rebuild down force. We'll see if Webber starts getting the upper hand on Vettel with these changes, as he had in early 2010.

Im hoping this will be the case! [-o<

[horse]

1) I doubt you are allowed to reprogram the ECU while in parc ferme.

2) They can have all the maps they want in the ECU now.

3) This is simple way for the FIA to get some kind of reduction in off throttle mapping at the next race.

It is just not clear how and when the teams will be able to change maps.

Brian

This pitpass article seems to agree with my interpretation, Brian. I don't know how many maps you can store in the ECU, but if they are having to use the rule loophole to reset them between quali and the race then it must be finite.

“As it would be too time-consuming to plug a laptop in during a pitstop,” he continued, “this regulation effectively means that, for Valencia, cars should run the same suite of engine maps throughout qualifying and the race – as opposed to before, when you could plug in a laptop, re-configure the ECU mappings for quali, and then reset them in parc ferme ahead of the race.”

Referring to Charlie Whiting’s latest letter to the teams, he added: “The FIA’s correspondence feels that Article 34.1 of the Sporting Regulations, which states that, in parc ferme, ‘on board electrical units may be freely accessed via a physical connection to the car’, is being interpreted inconsistently by the teams, so this re-interpretation effectively closes that loophole.”

[hardingfv32]

That makes sense. They can always down load data, but I guess uploading was gray.

Thanks
Brian

[hardingfv32]

I'm not sure that expecting the driver to hold the throttle down a little is going to work.

Presently when the driver gets off the throttle that part of the engine's map associated with off throttle blowing begins. When the driver gets back on the throttle he has a normal throttle map. It is a well locate on and off position.

Now you are proposing that he find a throttle position just off 0% throttle. How does he do this rapidly at say his braking point? This is a very fast foot movement and at this point, not requiring an accurate lift stopping point.

Is the driver's foot that steady? What about jarring curbs, etc.? What are the complications of falling into the idle position accidently?

I know these are great drivers, but this does not seem user friendly in the slightest.

Brian

[Shrieker]

Brian, +1. Also while braking, the g-forces involved means that you actually have to prevent your feet from pressing the pedals too much.

AFAIK the rules don't allow detents in the pedals either, so i can't really see a practical way to use EBD under braking and cornering. But then, this is F1 so you never know...

[raymondu999]

I have a question that will either be the next big controversy, or will make me look like a massive idiot. Couldn't they do something with the clutch though? I mean technically the start procedure (rev it to about 13,000rpm, drop one clutch, release the other slowly) is a manual overrun, no?

[feynman]

I'm not sure that expecting the driver to hold the throttle down a little is going to work.

Presently when the driver gets off the throttle that part of the engine's map associated with off throttle blowing begins. When the driver gets back on the throttle he has a normal throttle map. It is a well locate on and off position.

Now you are proposing that he find a throttle position just off 0% throttle. How does he do this rapidly at say his braking point? This is a very fast foot movement and at this point, not requiring an accurate lift stopping point.

Here is what I meant by "long" throttle pedal:



To all intents and purposes the engine response to throttle position remains identical, but there is an extra coupla inches of mechanical dead zone added. Basically he would really need to pull his leg way back to get "fully off" the throttle, it gives a big band that is not "fully off", but barely on, and that lets the engine map continue to ferociously hot or cold blow the diffuser.

Again all of this based on the notion that throttle response doesn't have to be linear (can't see the rule that says it must), and that the FIA exhaust/diffuser regulation only kicks in at "fully off the throttle", i.e. idling at 0% (haven't actually seen the technical note, just going on what James Allison said)

[hardingfv32]

Disengage the clutch? We still have KERS that must be driven and charged. How about the down shifts?

I think at a minimum anything you do at this point, assuming it is legal, will have to be stealth. The FIA wants this stopped and that objection is what you are trying to work around.

Brian

[hardingfv32]

"Here is what I meant by "long" throttle pedal:"

Yes, that is a good idea and would make a legitimate throttle map as it can be replicated in a mechanical form.

Obviously the throttle travel is well refined at this point and the actual throttle pedal has a limited range of motion. I wonder what how much of the throttle map can be set aside for your proposal.

Brian

[bot6]

I think the reason for the engine map limitations is so that the FIA has only one set of engine maps to check at the end of the race in order to enforce the "no blowing" rule, instead of two sets (one at quali, one at race) which would be twice as much work for Charlie and his boys.

And if they enforce the ban by checking the engine maps on the car ECUs, then ideas like a "long throttle" or any other way to circumvent the 0% throttle spec would be found out and deemed illegal using the "no F-duct" rule saying the driver can't act to change the car aero.

[gridwalker]

With reference to the long throttle : Why should a driver struggle to find the point where the throttle switches from blowing to acceleration? It is relatively easy to set a point on the pedal movement where it requires a little more pressure than usual to continue moving (possibly giving a slight tactile click to indicate when the pedal moves past that point) so drivers have some feedback to indicate the pedal position.

If Ferrari can engineer a pedal that depresses further when DRS is enabled, setting a "click-point" on the long-pedal to indicate the change of throttle mode would be a walk in the park. This is still entirely dependent upon the throttle map passing the FIA's scrutiny, but it would help prevent any confusion over the where blowing stops and acceleration begins.

[raymondu999]

Couldn't a driver brake, go full throttle, and full clutch all at once during heavy braking? That would kind of "simulate" off throttle blowing, no?

[bot6]

yup, but you'd need three feet.