Kimi vs. Fisichella (driving styles)

[f1.redbaron]

I was watching the replay of the last 3 laps of last week's GP. I noticed that, on more than one occasion, Kimi had both of his feet on his car's pedals - i.e. he was braking and accelerating at the same time. Fisichella, on the other hand, had done this only once if I'm not mistaken.

I was wondering, is there an advantage of accelerating and braking at the same time? What I mean is, if one foot is braking as the driver is about to enter a turn, and the other one accelerating (albeit, slightly) at the same time, will this save time when the driver comes out of a turn to accelerate - say 1/100th of a second or more as opposed to when the foot is only resting and waiting for the other one to let go of the brakes?

I'm gonna try to make my question simpler. A normal, everyday driver is driving (a car with automatic transmission) and sees a red light. Now, if he had his right foot on the accelerator pedal, and his left one just resting on the brake pedal, he would, obviously, need less time to stop, than if he was just resting his left foot on the footrest. Is that what Kimi was trying to achieve? If so, doesn't that result in a higher brake pad wear? But I guess, it didn't make much difference when entering the last lap of the race.

[johny]

what happened in last lap is fisi brake too much in the last chicane so kimi exited very very close to him.

dunno if you could do that in a f1 car today but i read villeneuve saying that he lost so many time doing that because the tc were launched

[Monstrobolaxa]

Probably you saw it while braking for a corner....M. Schumacher was one of the first drivers to use this technik...according to what I once read in a F1 Racing (magazine) article it helps do control the car preventing it from having a violent response to hard braking, i.e. it won't become unstable.

It does mean higher brake wear but at the end of the race...and with the brake wear sensors the team can monitor the wear....so he had a green light to do it.

Under aceleration he wasn't doing it for sure....it would heat up the brakes and would be loosing him time.

[DaveKillens]

Monstro, I agree. I also heard of this technique, where if you apply some gas as you are braking, the car actually is more stable and less prone to darting and wandering under braking.
I use this very same technique myself in sim racing, and yes, it works there. In diffficult corners where the car appears to be more unstable under braking, it allows consistency and security. It probably adds a little distance, but considering that usually this technique is done only in certain braking areas, the added stability and security of not going off line is worth the small loss in time.

[mep]

DaveKillens wrote: I use this very same technique myself in sim racing

On wich simulation do you use this and in wich corners?

[Monstrobolaxa]

Probably slow corners....with heavy braking areas....

[manchild]

This also probably enables better "lift-off" once the braking stops, sort of accumulating of power before it is transmitted to wheels - putting engine in higher RPM regime in order to get faster response later - similar to purpose of heel-toe technique. TC obviously enables this to be done less tricky by reducing the risk of spin.

[f1.redbaron]

This also probably enables better "lift-off" once the braking stops, sort of accumulating of power before it is transmitted to wheels - putting engine in higher RPM regime in order to get faster response later - similar to purpose of heel-toe technique. TC obviously enables this to be done less tricky by reducing the risk of spin.

That was what I though, at first. But DaveKillens and Monstrobolaxa make a valid point, too. I, actually, had the chance to try that out today. I drove at about 120km/h when I entered this on-ramp (for a different hwy) that is rated for 70km/h. Normally, I break and then accelerate only as I'm exiting the apex (brakes off). This time I did what Kimi did - I was braking and accelerating at the same time. It may sound wierd, maybe it is just in my head, but I kind of felt that I had the greater control over the car (btw, couple of months ago I tried breaking with my left foot, and I liked it, so I still do it sometimes...it isn't very comfortable, but it is more fun). Of course, I don't think that I will continue to do that anymore (brakes and accelerator on at the same time)...after all, I don't want to spend my paychecks on brakes

[Monstrobolaxa]

This also probably enables better "lift-off" once the braking stops, sort of accumulating of power before it is transmitted to wheels - putting engine in higher RPM regime in order to get faster response later - similar to purpose of heel-toe technique. TC obviously enables this to be done less tricky by reducing the risk of spin.

The only thing...is that you're not putting the engine in higher rpm...you're only giving it extra fuel!...and whan taking our foot off the brake you'll have a big "jump" in the rpms...

Just look at it this way the wheels are connected to the engine...so if the wheels are loosing speed the engine will also! It's like when your driving a standard gearbox car....when going down hill you can take your foot of the gas and the engine can reach 3000-4000 rpm! It's the wheels driving the engine...not gas! The gas entering the engine is basicly the same as if the car was at idle.

Same thing here....foot on gas and braking...the engine is slowedd down! it will only be usefull when taking the foot of the brake...and this will give a very big increase in rpm!

(Don't know if it was what you meant but I understood that you meant the foot on the gas would increase the rpms while braking...so if I understood wrongly forgive me! )

[Guest]

I think its called trailbraking and it enables you to alter the cars behaviour in a corner depending on your brakebalance setting.

/ Fx

[jaslfc]

its called left foot braking. Used in karting and mainly rally driving. It is not an easy technique to master. Wat is does is lower the response time(taking the right foot out of the accelerator and puting it on to the brakes) by doing this u are able to brake slightly later and power out earlier... then second thing is that it enables u to have a better control by playing with the accelerator and the brakes.. i heard from an interview that in the suzuka esses.. micheal shumacher was a few tenths faster than barrichello because of his left foot breaking and soon after that barichello started using it too..

[manchild]

I agree about what Dave and Monstro said and I've only posted that as possible addition to benefits of this technique.

I had it mind downshifting during braking and use of this technique to keep engine in highest possible rpm - keeping accelerator pressed and relying on TC to prevent spin once the braking stops and when input torque drops below the output torque (driver can’t outsmart TC and differential control when it matters output and specially input torque). Bad side of this is obviously heavier fuel consumption, general overheating (engine, brakes) and brake wear.

I also had in mind time between shifts and time of each shifting. Something like locking brakes on airplane before engine makes enough thrust and than releasing them, naturally in F1 case only for those precious moments when driver’s foot taken of the accelerator would mean loss of performance.

[Monstrobolaxa]

Trail braking is braking while cornering....while turning into the corner...not braking and acelerating at the same time!

[manchild]

I know that, I had in mind keeping engine on highest possible regime so that it can pick up more efficiently once the braking stops and acceleration starts.

When I said shifting I meant only shifting down... sorry for that I thought it was understood.

[Scuderia_Russ]

I always overlap my throtle and braking when i'm karting. Quickest way around a circuit for me.