ACO announces Adjustments to Performance for Le Mans

There has been a lot of chatter in recent days, following the publication by the ACO of the Performance Adjustments in advance of the Le Mans 24 hours, for which scrutineering is due to begin in just two weeks time. My sympathies lie with all concerned. First, with the ACO, who is coming under criticism for doing ‘too little, too late’. Second, with the smaller teams who now have very little time to test out different engine mappings and the impact on fuel consumption and tyre wear of running with less weight and more power. And third with the major manufacturers, whose advantage over the rest has (to an extent still to be determined) been diminished.

For the spectators and media though, it can only be good news. The media can now go into a frenzy of claim and counter-claim and the spectators have the prospect of a closer race to witness, with all kinds of possibilities now in prospect for the great race.

The detail of the adjustments can be found elsewhere on the web and if you are savvy enough to get here, then you’ll be able to read the exact changes that have been mandated. I also commend to you the interview (published both in English and French) with Vincent Beaumesnil (sporting manager of the ACO) justifying the adjustments. My purpose here is merely to comment.

First, a defence of the ACO. Article 1.3 of the 2011 Sporting Regulations (first issued in December 2010) was clear enough: the adjustments would be applied to ‘the slower technologies’ and there was no suggestion that the faster cars would be ‘reeled in’. So the idea that the ACO was going to adjust the performance of the diesels to slow them down to the ‘target lap time’ of 3 mins 30 secs was never (in my opinion) an objective for the ACO. I’ll admit that it was their stated objective when the Technical Regulations were written in the first place, but not the objective of the mid-season performance adjustment.

So suggestions that the ACO missed an opportunity to slow down the diesels are, quite simply, wrong.

It was equally obvious therefore that the impact of the performance adjustment would fall on the teams using the slower technologies. So the time to complain was in December and January (or in the many meetings that the ACO held with Le Mans entrants beforehand), not now that the actual adjustments are made known.

The regulations also made clear that only race data would be analysed, and adjustments would only be made after two races had taken place. Sebring and Spa were the first two rounds of the ILMC, but the ACO also had the chance to analyse data from Long Beach (ALMS) and Paul Ricard (LMS), but of course there were no diesel-engined cars at either of these events. Data from practice and qualifying sessions, and the Le Mans Test Day was inadmissible. From looking at the calendar, it was apparent that time would be tight between the data being available to analyse and the outcome of the organiser’s deliberations being made known.

The way I look at it - and for the moment focussing purely on LMP1 cars, the adjustments fall into two categories: firstly the diameter of the refuelling hose (or at least the orifice through which the fuel has to pass) and secondly the engine performance parameters.

The diameter of the refuelling hose obviously has no impact on lap times, but will affect the amount of time spent in the pits refuelling. Now I am no expert at fluid dynamics (I believe the term is rheology), but by reducing the size of the orifice through which the fuel must flow for the diesels by 3mm (to 25mm) and by increasing it for the petrol-powered teams by 10mm (to 38mm), the ACO has made a significant impact, without demanding the teams to make any change to the configuration of the car itself.

By my somewhat rough and ready calculation, the fuel flow rate for the diesels will be roughly half that for petrol-engined cars. In other words, petrol will flow (less viscosity, through a larger restrictor) at a rate of nearly 3 litres per second, but for the diesels at about 1½ litres per second. This will mean that a fuel-only stop will cost a petrol team 25 seconds (depending on how much fuel is left in the tank when the car stops), whereas a diesel car will be at rest for around 50 seconds.

Reassuringly, I did this calculation before reading the interview with Beaumesnil, who also suggested that the difference in refuelling time would be “over 22 seconds, the equivalent of two seconds a lap”. Over the course of 24 hours, this is like giving a diesel car around three and a half laps penalty. If that’s not “reeling in the diesels”, then what is?

The other category of change is the reduced weight / increased air restrictor combination, and this is what leads me to sympathise with the petrol-fuelled privateers. It’s now decision-time. Run at the reduced weight and risk a problem occurring in the race that hasn’t previously been encountered? Maybe the car is not at the weight limit anyway; in which case, the increased restrictor could mean additional engine development costs and changed mappings. But doing nothing is not really an option either - the extra air entering the engine should provide enough horsepower to reduce lap-times by up to a couple of seconds. But would Pescarolo or Rebellion (for example) want to come to Le Mans with a different package from the Test Day without proper testing? It is a real dilemma.

The trouble with all this performance fiddling, is that it makes comparisons difficult. Lap times obviously can’t be compared from last year to this, but nor really can pit stop times. “Time spent in pits” is one of those interesting statistics that I collect. But when I look back at the amount of time spent by cars in the pits over the years, I find myself increasingly comparing apples with pears. In the days of Group C, the fuel fill rate was one litre per second, and the tank (under the first iteration of the regulations), took two minutes to fill. More recently, the nonsense with the restrictions on the number of mechanics changing the tyres has made it meaningless to compare pit stop times with those from the early years of this decade.

This year, however, the fact that fuel is allowed to flow into some cars more quickly than others, will make "time spent in pits" even more irrelevant as a measure of a team's efficiency - although it may well have a bearing on the outcome of the race.

There are other aspects of the adjustments which also bear discussion, such as the reduced weight of the Oreca Peugeot (yes, the one that won at Sebring) and the LMP2 changes (which seem to penalise the slower cars), but I think I will leave those for another occasion.

What do you think?

Le Mans 1981 - personal recollections

In October last year, I posted some recollections of the first race I ever attended, the 1967 Race of Champions. With Le Mans 2011 fast approaching, I thought readers might be interested to read memories of my first trip there to see the fabled Vingt-Quatre Heures du Mans in 1981. I was already a keen follower of motor-racing, having attended Grands Prix at Silverstone, Brands Hatch, Austria and Monaco, as well as other races at most of the UK’s major circuits. On the endurance front, I first went to the BOAC 1000 at Brands Hatch in 1972, and had seen quite a few 1,000kms and six hour races at Brands and Silverstone after that. I was also able to visit the 1,000kms at Monza in 1980 (won by Alain de Cadenet and Desiré Wilson by just a handful of seconds).

I remember that a friend of mine from university, Steve Davison, had suggested a couple of times that we should go to Le Mans together, and finally we agreed to go ahead and do it. At the time I was living and working in Redhill, Surrey, and a work colleague of mine at that time, Malcolm Gimblett, also decided to come along.

So we booked ourselves a ferry (Portsmouth to Le Havre), got some tickets and set off; the three of us, with a tent each, in my Alfasud, heading for the White Panorama campsite. We left in the morning of Wednesday 10th June, with me driving, and Malcolm (who had longer legs) alongside advising on whether it was safe to overtake or not. I felt his indecisiveness and caution were slowing us down, though, so after a stop for fuel, we squashed Malcolm into the back seat, and Steve (who had ‘navigated’ for me on some University-run treasure hunts in the past) took over as co-driver. Most of the road down from Le Havre was quite clear - a couple of helpful locals flashing headlamps to warn of ‘Gendarmes ahead’ - and we made good progress. Even so, night was falling as we sought out the ‘Parking Blanc’ signs, which we reckoned we needed to follow, and finally we found our campsite just after 10pm. The plots were marked, but un-numbered, so we found a good-looking flat-ish plot, parked the car and decided that, as we could hear practice in full flow and the fact that it was due to continue until 11pm, we’d find the track and put the tents up later, despite Malcolm’s warning to us: “do you really think that’s wise?”

As it was so late, the gates were open, so we didn’t have to show our tickets, but simply scrambled up a bank and found ourselves on the outside of the circuit, just past the Dunlop Bridge. It’s one of those memories that has remained clear in my mind ever since. The image of cars having just crested the rise, appearing from underneath that famous bridge and thundering away from us, downhill toward the Esses has not faded. That final half-hour or so of practice; my first encounter with the narcotic that is Le Mans, was truly intoxicating. They were fast - so fast - and they were spectacular - headlights illuminating the way and turbo-chargers flaming out as drivers lifted off the throttle before the Esses. All mighty impressive.

After practice ended, we put the tents up, and on the Thursday morning Steve went off to buy himself an admission ticket. I can’t remember the details now, but I think I had sorted the camping and entrance tickets for Malcolm and me (probably through ‘Just Tickets’), but Steve hadn’t. No worries, we thought, until Steve came back, complaining mildly that he had had to pay rather more than we had for ours. So we compared them and discovered that his was “Enceintes General” and ours “Enceintes Virages”. We went back and established that this meant that Steve could get into the start-finish area in front of the main grandstands, but that Malcolm and I could not. This would only apply for the race itself, though: for practice this evening we would be able to go anywhere.


Lancia MonteCarlo - note token barrier to keep crowd out!

At the time, I didn’t think much about the fact that we could get pretty much anywhere we liked during Thursday. The paddock in those days was spread out behind the pits, which were not the sophisticated and well-equipped garages of today. The teams were camped under awnings, where they worked on the cars between practices sessions and the cars had to be pushed round into the pit lane, to sit in front of the pit boxes, at the start of every practice session.

As a result spectators could wander around the transporters, awnings and motorhomes practically at will, and cars could be easily seen as they were being worked on.

We went up onto the top of the pits to watch practice for the support race (Renault 5 Turbos), then through the tunnel to the outside of the circuit to watch final practice (which was from 6pm to 10pm).  


Tiff Needell in the IBEC, entering the pits straight

Then it was down to the funfair, located on the outside of the Esses in those days. Although I had been to funfairs in England before, I wasn’t expecting the sheer size and variety of things on offer at Le Mans. And the range of folk that were there was simply astonishing. It seemed to me that some were there specifically for the funfair, who found the car noise somewhat distracting, others whose high-heels and furs prevented them from leaving the relative safety of the ACO ‘Welcome’ building and still more dedicated race-fans like myself, trying to get the most from every experience.

I was reminded of Epsom Downs on Derby Day (when it used to be on a Wednesday), and the infield of the racecourse was open to everyone, and people turned up in their tens of thousands, not all interested in horse racing, not all honest, but every one contributing to the atmosphere of the event, making it something unique.

On Friday we went exploring into town to buy provisions. We drove round the track, at least as far as you could, we had a beer in the Restaurant des Vint-Quatre Heures, and then we went back and looked around the paddock some more, taking photos.


Derek Bell - can you imagine him allowing himself to be photographed like this nowadays?





Brian Redman

Saturday morning was bright and sunny - in fact the whole weekend was a scorcher. Armed with his ‘posh’ ticket, Steve went off to the grandstand area to watch the startline jollities; Malcolm and I trudged over the Dunlop Bridge and went down to watch the start from the outside of the first part of the Esses - on a well-inclined slope, looking straight at the cars as they descended the hill from the Dunlop Bridge towards the Esses.

Pace lap - Mass ahead of Ickx in the Porsches

We split up soon after the start… I continued to walk up to Tertre Rouge - watching from the inside, then through the tunnel there to the outside of the circuit. This was the first year that a pace car was used to neutralise the race, and I remember several incidents which required its deployment. It was only on Sunday morning, when I bought the newspaper, that I learned of the death of Jean-Louis Lafosse in the Rondeau. And only on the ferry back did I discover that a marshal had also been killed in separate accident earlier in the race. Such was the way of things in those days.

I headed back to the Esses, on the outside of the circuit, ignoring the dubious pleasures of the funfair while there was a race going on, as darkness began to fall.

Around 2am, I must admit to snoozing on the bank on the outside of the circuit, just before Tertre Rouge… it was completely dark and hard to see the numbers on the sides of the cars. I kept my notebook with me though, and had an appointment most hours (on the half-hour) to listen to Bob Constanduros give his English language update over the loudspeakers.

As dawn broke, I decided it was time to visit other parts of the circuit, so started the walk from the Esses, down to the Dunlop curve and out onto the service road behind the grandstands (not forgetting my ‘contre-marque’). Not being allowed into the ‘tribune area’ I continued the walk until the point where holders of the “Virages” ticket were allowed back in. I watched the cars braking for the Ford Chicane and followed the track as far as the spectator enclosure went, in the direction Maison Blanche, which in those days was not very far. Then it was back onto the public road (aware that this used to be the track, before the Porsche Curves were built) all the way to the crossroads (now a roundabout) where the road to Arnage leads off to the right.

This was the road I took, conscious that I was headed away from the track, but plodding on with determined resolution. Over the level crossing, I turned left, following the sign to Virages Arnage and Mulsanne. It took me the best part of three hours, as I remember, and the merguez at Arnage when I finally got there was very welcome indeed. Arnage was wonderful in the morning sunshine - the marshals had a stork in the infield area, I remember.

I found a man selling Le Maine Libre and spent some time sitting on the bank overlooking Arnage corner. This was one of the few places where you could hear the loudspeakers and see the track at the same time, as the cars were off the throttle and not quite so loud. This enabled me to piece together some of what had been happening during the race and to recover after my long walk.

I then felt strong enough to continue my trek around the track, walking up to Indianapolis, then found a path leading into the trees, which seemed to be heading in roughly the direction of Mulsanne Corner.

The path quickly petered out, but the cover of the trees provided a welcome respite from the heat of the day, which was building rapidly. I could see Armco barrier to my left and the flash of cars going past, through the trees, but the forest was too dense to get very close. There were a couple of rolls of barbed wire to hop over, I remember, but a couple of people way ahead of me, who seemed to know where they were going encouraged me to persevere. Then a few houses came into view, and eventually I came out at a large woodshed, and was able to find my way back into a proper spectator enclosure at the exit to Mulsanne corner.

From here I could see the signalling area, and a suddenly gained another fascinating insight into how Le Mans works. One car actually stopped and the driver had an animated conversation with the signallers, before heading off again. Throughout it all, the Porsche 936/81 of Jacky Ickx and Derek Bell was running like clockwork and was getting further and further ahead of the opposition.

Bell in the winning Porsche at Tertre Rouge early in the race

I managed to find my way back to Indianapolis on the public road designed for such a journey - which saved me having to stumble over any more tree roots and pine cones, but deprived me of the view of the cars through the trees - and I watched the finish of the race from Arnage. By my watch, the flag marshals started invading the track waving with their flags a minute or two before four o’clock, which by my reckoning meant that the cars were still racing, which didn’t quite seem safe somehow. On the other hand, to watch the drivers respond, slowing down and acknowledging the marshals, stirred the emotions in a way that I wasn’t expecting. The sheer fatigue, shared by everyone, provided a huge sense of achievement. It brought a new angle to the meaning of “endurance”, more than just the achievement of winning the race, or a class, but just being there at the end, that even today I find difficult to put into words. As the cars passed on their final lap, the public was able to come onto the track as well, which gave me an ideal opportunity to walk back to the start-finish area on the track (a mere 4 kms), rather than going the long way round. Then it was back to the campsite, and I’m sure we must have gone out for a meal somewhere, but I remember only getting very grumpy with Malcolm and Steve. Not their fault, more the fact that I was unused to dealing with sleep deprivation.

We drove back to Le Havre on Monday, taking a night ferry back and arriving in Portsmouth on Tuesday morning. And to start making plans to revisit in 1982.

(All photos copyright from my private collection)