46 replies to this topic

[racersteven]

After the Monaco GP Nigel Mansell claims that the Brawn GP cars have the best Acceleration off the line and out of slow corners he has seen since his williams FW-14b. I would think that the 2003-5 V-10 cars would have better Acceleration. I seem to remember the 2003-5 Renaults getting great starts and having great acceleration. I would think 900 hp with traction l and launch control would beat the Brawn Gp or the williams fw-14b.

Edited by racersteven, 22 October 2009 - 00:49.

[gruntguru]

After the Monaco GP Nigel Mansell claims that the Brawn GP cars have the best Acceleration off the line and out of slow corners he has seen since his williams FW-14b. I would think that the 2003-5 V-10 cars would have better Acceleration. I seem to remember the 2003-5 Renaults getting great starts and having great acceleration. I would think 900 hp with traction l and launch control would beat the Brawn Gp or the williams fw-14b.

For any of the three cars you mention, off-the-line acceleration will be traction limited so power becomes irrelevant. The key factors will be tyre coefficient of friction, control of slip to achieve the maximum coefficient of friction, vehicle mass and vertical force at the tyre contact patch. The last of these is very complex and will depend on static weight distribution, weight transfer under acceleration and transient factors like anti-squat.

In short, there are a number of things that Brawn (and the tyre companies) might have improved since the 2005 cars and only one disadvantage to Brawn - no launch control.

Edited by gruntguru, 24 October 2009 - 11:14.

[desmo]

Are we now assuming TC/LC is actually a non-issue now in F1? I guess it's better that way.

[benrapp]

Are we now assuming TC/LC is actually a non-issue now in F1? I guess it's better that way.

Surely, unless you think they can game the standard ECU, it must be a non-issue?

[Ross Stonefeld]

And that they have a form of launch control anyways?

[Kalmake]

2003/2005 didn't have slicks.

Although TC is superior to human, maybe they have improved driveability to make the difference smaller. There's a Schumacher quote from -93(?) stating they were two seconds a lap slower with TC off. It's understandable that Mansell would recall his TCed Williams, when being impressed by the Brawn. I don't think he was making a serious statement however.

[imaginesix]

I seem to remember the 2003-5 Renaults getting great starts and having great acceleration.

They didn't have great acceration, they had a great response time. I believe those are the cars that had launch control timed automatically off the starting lights.

[Scotracer]

The fastest off-the-line accelerating F1 cars of all time were in 2006 when they had the best electronics and the midst of a tyre war. Even though they were 200BHP down.

[murpia]

Why assume good launches always involve electronic assistance?

Weight distribution and mechanical solutions for progressive clutch engagement offer a lot.

Regards, Ian

[gruntguru]

Why assume good launches always involve electronic assistance?

Weight distribution and mechanical solutions for progressive clutch engagement offer a lot.

Regards, Ian

No electronics in a top fuel dragster, 0-100 mph in 0.7 sec.

[racersteven]

They didn't have great acceration, they had a great response time. I believe those are the cars that had launch control timed automatically off the starting lights.

I could be wrong but I thought one of the strong points of the 2002-5 era Renaults was their Acceleration off corners. In the 2004 German GP Jenson Button had a very difficult time trying to pass F. Alonso because the Renault was getting better drive off the corners making it difficult for the Bar Honda to use its Top speed advantage to pass the Renault. In Imola in 2005 M.chumacher said the same thing about the Renault.

[alexbiker]

Slicks. No grooves.

[Kalmake]

I could be wrong but I thought one of the strong points of the 2002-5 era Renaults was their Acceleration off corners. In the 2004 German GP Jenson Button had a very difficult time trying to pass F. Alonso because the Renault was getting better drive off the corners making it difficult for the Bar Honda to use its Top speed advantage to pass the Renault. In Imola in 2005 M.chumacher said the same thing about the Renault.

IIRC general understanding at the time was that Michelin had better longitudinal grip than Bridgestone. Renault also had more rear weight bias than other cars.

[Tenmantaylor]

Maybe he just meant in composure relative to the other cars rather than absolute terms. Not like hes got access to all the necessary data unless our Nige has hacked into some special data channel we dont know about?

[racersteven]

I found some speed trap information for the S/F line at Monaco which should be a good inditication of Acceleration. 1993. A .Prost Williams FW-15 158 mph. 2000 Mika Hakkinen McLaren 160 mph. 2004 R Schumacher Willims BMW 171 Mph !! 2006 M Schumacher 161 mph . And in 2009 L.Hamilton 168 MPH and Jenson Button 161 mph. All the cars are similar except for the 2004 Williams and it seems that Kers dose make a big difference in Acceleration as Lewis Hamiton was 7 mph faster than the brawn at the S/F.

[DaveW]

IIRC general understanding at the time was that Michelin had better longitudinal grip than Bridgestone. Renault also had more rear weight bias than other cars.

& Michelin runners had the tyre stiffness split to support a rear weight bias....

The red & silver cars appear consistently to make better race starts than most in 2009. It has occurred to me that it would be simple to program KERS to work as a traction control device, especially if the regulators turned a blind eye (perhaps to promote KERS?). I wonder....

[alexbiker]

& Michelin runners had the tyre stiffness split to support a rear weight bias....

The red & silver cars appear consistently to make better race starts than most in 2009. It has occurred to me that it would be simple to program KERS to work as a traction control device, especially if the regulators turned a blind eye (perhaps to promote KERS?). I wonder....

Simple? How?

They can't even engage it off the line, until they hit a certain speed, IIRC - the limiting factor on an F1 car start being how low the revs are. The lower the revs, the faster the start unless you engage the anti-stall, see Brundle's "granny leaving the supermarket" vs "boy racer" start line piece a few years ago.

[DaveW]

Simple? How?

They can't even engage it off the line, until they hit a certain speed, IIRC - the limiting factor on an F1 car start being how low the revs are. The lower the revs, the faster the start unless you engage the anti-stall, see Brundle's "granny leaving the supermarket" vs "boy racer" start line piece a few years ago.

I think you refer to the speed limit imposed on increasing power to the rear wheels. I know of no direct regulation (other than the ban on traction control) to prevent KERS being charged when the vehicle is accelerating (i.e. diverting excess power from the rear wheels). I think everything required would be in place to make it reasonably simple to implement.

[Tony Matthews]

I think you refer to the speed limit imposed on increasing power to the rear wheels. I know of no direct regulation (other than the ban on traction control) to prevent KERS being charged when the vehicle is accelerating (i.e. diverting excess power from the rear wheels). I think everything required would be in place to make it reasonably simple to implement.

Surely the KERS system channels energy from braking - if it was to do it while accelerating it would be the complete opposite of what was intended, to make use of wasted energy.

[DaveW]

Surely the KERS system channels energy from braking - if it was to do it while accelerating it would be the complete opposite of what was intended, to make use of wasted energy.

You are quite correct, Tony, that is the intention, but KERS uses the drive train (rather than the brakes) as the energy source. An F1 engine is capable of delivering an excess of power at low speeds, so the option of controlling wheel spin must be tempting given that the necessary hardware is in place (& assuming that the regulators raise no objections). And certain teams do appear to execute spectacular launches from the start line with remarkable consistency.

[alexbiker]

I think you refer to the speed limit imposed on increasing power to the rear wheels. I know of no direct regulation (other than the ban on traction control) to prevent KERS being charged when the vehicle is accelerating (i.e. diverting excess power from the rear wheels). I think everything required would be in place to make it reasonably simple to implement.

The KERS system may only be powered by energy recovered by braking. That is one of the technical regs.

Which doesn't also excuse the nonsense of using the a drag to improve a start which is limited by the engine's ability to keep from stalling. That's the limit on the start until the engine hits the powerband, at which point the drivers short-shift and floor it. If they wanted to add drag, why not just wind the brake balance backwards and press that left-hand pedal?

The video on this sucks, but the audio tells you all about starting technique. Listen to it. Brundle's F1 Lessons

[DaveW]

The KERS system may only be powered by energy recovered by braking. That is one of the technical regs.

First, (just to be sure) KERS is actually an additional brake attached to the rear axle. If KERS is being charged at any time, it will be "braking" the vehicle (absorbing energy). Hence using it as an "alternative" traction control device would not breach the regulation you quote.

Which doesn't also excuse the nonsense of using the a drag to improve a start which is limited by the engine's ability to keep from stalling. That's the limit on the start until the engine hits the powerband, at which point the drivers short-shift and floor it. If they wanted to add drag, why not just wind the brake balance backwards and press that left-hand pedal?

Apologies, but I can't think the video is convincing evidence, because the vehicle Brundle used was not fitted with KERS. I don't find your "stalling" argument convincing either, because it would imply that the current ban on traction control is superfluous.

Using the rear friction brakes would work as an alternative to KERS, of course, provided a driver was capable of finding & maintaining the optimum slip ratio....

Both commentators & competitors have referred to the launch ability of the "KERS cars", but have attributed the superiority to power ADDED (the commentators have, anyway). This may be the case, but I could convince myself that the advantage becomes apparent before the vehicles reach 100 kph. I don't recall a "bogged" start by a KERS car, either.

[alexbiker]

First, (just to be sure) KERS is actually an additional brake attached to the rear axle. If KERS is being charged at any time, it will be "braking" the vehicle (absorbing energy). Hence using it as an "alternative" traction control device would not breach the regulation you quote.



Apologies, but I can't think the video is convincing evidence, because the vehicle Brundle used was not fitted with KERS. I don't find your "stalling" argument convincing either, because it would imply that the current ban on traction control is superfluous.

Using the rear friction brakes would work as an alternative to KERS, of course, provided a driver was capable of finding & maintaining the optimum slip ratio....

Both commentators & competitors have referred to the launch ability of the "KERS cars", but have attributed the superiority to power ADDED (the commentators have, anyway). This may be the case, but I could convince myself that the advantage becomes apparent before the vehicles reach 100 kph. I don't recall a "bogged" start by a KERS car, either.

Where to start - so much confused thinking. . .

Traction control acts as a spark-controlled limit on the engine power, so that you can run the optimal revs without either stalling or burning the tyres up - and it wasn't traction control, it was launch control. "Granny leaving the supermarket" was the fastest - so set the computer to do that and it won't stall, it won't spin the tyres up, you'll get formation starts. As we saw.

The technical regs only allow KERS to be used under braking. That's it. The whole plan you surmise is not only unworkable, it's impossible with the SECU.

Watch some of Hamilton's starts - he's bogged down. Better still, watch Heiki - he loses metres at the start and gains them right back in the KERS zone. When the power kicks in, back he comes.

[DaveW]

Where to start - so much confused thinking. . .

Traction control acts as a spark-controlled limit on the engine power, so that you can run the optimal revs without either stalling or burning the tyres up - and it wasn't traction control, it was launch control.

As you wish....

[murpia]

The way the F1 KERS regs are interpreted, you could indeed charge the KERS off the line with engine power, but only by pressing the brake pedal, and only above 100kph. That would reduce engine torque to the wheels.

Drivers have always had the ability to left foot brake to reduce wheelspin this way, rather than bylifting the throttle. But I never heard of anyone actually doing it. Not sure why, maybe it's more difficult to learn?

Regards, Ian

[DOF_power]

The Williams had active suspensions not just TC-LC.

Here's Prost "killing the diffuser".


The reason Mansell's car was so fast was because the AS would tilt the car backward increasing the rear mass bias and downforce on corner exits and then raise the car upwards and peel of the drag as the speed increased.

Such technology was also used in DTM/ITC (and IMSA GTP), and according to Dario Franchiti the internal computers knew the difference between the corner entry, mid-corner and exit and would modify the active tech accordingly.

The technology was far more advanced back then, let's not forget it.

[racersteven]

I found a track test of Nigel mansell Williams FW-14B from 1993 issue of Fast car . 0-60 in 2.2 seconds , 0 to 100 mph in 3.65 seconds and 0 to 150 in 7 seconds. I wonder if the Brawn GP could beat those numbers.

[gruntguru]

I found a track test of Nigel mansell Williams FW-14B from 1993 issue of Fast car . 0-60 in 2.2 seconds , 0 to 100 mph in 3.65 seconds and 0 to 150 in 7 seconds. I wonder if the Brawn GP could beat those numbers.

Average acceleration from 0-60 is 1.24g, from 60-100 is 1.25g and 100-150 is 0.70g. This would suggest that the car is traction limited to a speed considerably less than 150 mph and that drag is consuming well over half the power at 150mph.

And yes - I bet Brawn can beat at least some of those numbers.

Edited by gruntguru, 08 November 2009 - 03:28.

[Scotracer]

I found a track test of Nigel mansell Williams FW-14B from 1993 issue of Fast car . 0-60 in 2.2 seconds , 0 to 100 mph in 3.65 seconds and 0 to 150 in 7 seconds. I wonder if the Brawn GP could beat those numbers.

Given that the MP4-23 was given times all slower than that, and that the BMW F1.09 is rated as slower according to the BMW website, I doubt the Brawn is faster.

[BullHead]

Now tell me this, this is an issue in another thread in the RC forum: Tyre blankets in F1. Do they mean faster grid starts? I'm told they do and that's why F1 keeps them.

[desmo]

As absolute velocities are largely unimportant compared to relative velocities, I'm having trouble seeing why faster grid starts are important or how tire warmers are supposed to improve the spectators' experience.

[BullHead]

Well, I guess faster starts do improve the spectacle, as speed overall does, but will tyre warmers really assist this?

[GeorgeTheCar]

No electronics in a top fuel dragster, 0-100 mph in 0.7 sec.

No electronics but 50 years of fiddling with clutches, cams, timers, and other devices!

Diligence. Keep at anything long enough and you can get good at it!

[chdphd]

Here's a wee video I took at Spa this year of some drivers doing practice starts at the pit exit:

[gruntguru]

No electronics but 50 years of fiddling with clutches, cams, timers, and other devices!

Diligence. Keep at anything long enough and you can get good at it!

Not to mention a number of features not found in a F1 car: Tyres purpose built for 0-100, sticky track, 500kg of aero D.F. at 0mph, lots of contact-patch DF added by accelerating the Cg upwards at launch (is there a technical term for this anti-squat built into the tyres?) etc . . .

Edited by gruntguru, 25 November 2009 - 04:30.

[MikeTekRacing]

500kg of aero D.F. at 0mph

how do they get that?

[Ross Stonefeld]

Seconded.

[Kalmake]

Headwind?

[kikiturbo2]

exhaust gasses?

[Tony Matthews]

exhaust gasses?

Could well be...

[Kalmake]

Yes it is.

Here's some takeoffs in super slow motion:

[Silver Surfer]

Yes it is.

Here's some takeoffs in super slow motion:

A few different F1 tests:


2001 Jaguar F1 car:

Road & Track Magazine of March 2001 - Road test for 2000 Jaguar R1 Formula One car

Horsepower 800 bhp @ 17,500

0-60 mph @ 2.7 sec (100 kph)

0-100 mph @ 4.2 sec (160 kph)

0-160 mph @ 6.2 sec (255 kph)

0-180 mph @ 9.4 sec (290 kph)

Quarter mile run @ 9.4 sec @ 181 mph

Stopping distance from 60 mph (100 kph) @ 72 ft (22 meters)

Maximum lateral acceleration on skidpad 4.30g+


Test of a 2005 Renault F1 car:

0 to 100 km/h: 1.9 seconds

0 to 200 km/h: 3.9 seconds

0 to 300 km/h: 8.4 seconds



Test of a 2006 Renault F1 car:

0 to 100 km/h (62 mph): 1.7 seconds

0 to 200 km/h (124 mph): 3.8 seconds

0 to 300 km/h (186 mph): 8.6 seconds


Test of a 2007 Honda F1 car:

0-60 mph @ 2.8 sec (100 kph)

0-100 mph @ 4.1 sec (160 kph)

Quarter mile run @ 9.0 sec @ 161 mph

[Canuck]

Is it odd that the Honda is more than a second off the 0-60 pace?

[Scotracer]

A few different F1 tests:


2001 Jaguar F1 car:

Road & Track Magazine of March 2001 - Road test for 2000 Jaguar R1 Formula One car

Horsepower 800 bhp @ 17,500

0-60 mph @ 2.7 sec (100 kph)

0-100 mph @ 4.2 sec (160 kph)

0-160 mph @ 6.2 sec (255 kph)

0-180 mph @ 9.4 sec (290 kph)

Quarter mile run @ 9.4 sec @ 181 mph

Stopping distance from 60 mph (100 kph) @ 72 ft (22 meters)

Maximum lateral acceleration on skidpad 4.30g+


Test of a 2005 Renault F1 car:

0 to 100 km/h: 1.9 seconds

0 to 200 km/h: 3.9 seconds

0 to 300 km/h: 8.4 seconds



Test of a 2006 Renault F1 car:

0 to 100 km/h (62 mph): 1.7 seconds

0 to 200 km/h (124 mph): 3.8 seconds

0 to 300 km/h (186 mph): 8.6 seconds


Test of a 2007 Honda F1 car:

0-60 mph @ 2.8 sec (100 kph)

0-100 mph @ 4.1 sec (160 kph)

Quarter mile run @ 9.0 sec @ 161 mph

Please allow us to verify that data. AFAIK the 2006 Renault could do 0-100km/h in 2.1 seconds.

Is it odd that the Honda is more than a second off the 0-60 pace?

No launch control in 2007 and control tyres.

Edited by Scotracer, 02 December 2009 - 18:59.

[racersteven]

Silver surfer where do you get the performance numbers for the 2005 and 2006 Renault tests ? I know that the numbers for the 2000 Jag R1 in Road & Track were an estimate as Jaguar would not allow Road & Track to do a full test. In 2003 Autocar did drive the Jaguar R3 for its 0 to100 issue and it went from o to 100 mph in 4.0 seconds.

Edited by racersteven, 03 December 2009 - 02:15.

[Ross Stonefeld]

The spec ECU didn't come until 2008, but 2007 did have control tires.

[Greg Locock]

So, we have some dodgy numbers from some dodgy sources that may or may not represent the same sort of track conditions and vehicle setups.

Is anybody else struggling to see why the 0-60 time of cars under the above circumstances proves anything? Given, of course, that F1 cars care about 0-60 times like I care about the the price of sliced white bread?