Performance Equalisation In GT1 Of The ALMS In 2006
© Gary Horrocks

When the 2006 American Le Mans Series season is reflected upon, it is unfortunate, but people will likely forget about the battles that took place on the track. Instead, they will remember the public fighting and squabbling over the regulations, and the almost race by race changes that occurred during the season, especially in the GT1 class.

To the casual race fan, and even those more involved, the regulation changes, Balance of Performance (IMSA), or performance balancing, whatever it was called, really caused some grief and put a damper on the show. While it wasn’t a pleasant task for anyone, it was something that was necessary for the class to survive. Was it successful? That’s another question altogether.

The chief person in charge of technical regulations is the Executive Director of IMSA, Doug Robinson. “To be in my position, you have to have pretty thick skin. I equate it to being a referee in a sporting event. You are a necessary part of the sport and the decisions that are made can influence the outcome.

“Any time you try to embrace new technology and avoid being a “spec” series, it adds to the complexity. Hopefully in the end, we provide a highly visible forum for our teams, manufacturers, and sponsors to showcase their wares. I know my decisions will never be received with 100% agreement, but that doesn’t matter. I have a job to do and if I feel I made the correct decision at the time, I’m fine with it. I make no excuses and welcome comments from fans and competitors alike. In hindsight, yes, things could be different, but you don’t have that luxury. You just have to make a decision and go with it.”

And go with it, they did. “After Sebring, it was evident that the Corvettes were kicking the Astons' butt in GT1,” said Robinson. “We had already given Aston a 25 kilo break, as we believed they would have to work with Pirelli in order to get up to speed. We, as in IMSA, were willing to give them some more limited help in order to make them competitive.” So, for both Houston and Mid Ohio, the Aston Martin entries were running 50kg lighter than the ‘Vettes, with both cars running identical 31.8 mm restrictors. And the results were the same – the Corvettes finished on top.

As the season went on, it seemed as if the regulations changed for either a Corvette or an Aston every race. To many, it was over the top. After all, “pure” sportscar racing never had equalization formulae. But, what do you think restrictors are? They are nothing more than attempts at equalizing the performance capabilities of cars of varying capabilities.

The following, courtesy of Aston Martin Racing, documents the changes in the GT1 class regulations that took place during the year:

Note that early in the season, pre Le Mans, the Corvette stayed the same. It wasn’t until after the teams returned from France that the Corvettes were directly affected by the regulation changes.

After seeing the dominance of the Corvettes in the early season, the IMSA officials continued to add performance restrictions on the yellow cars, until it came to a point where it was almost a foregone conclusion for a few races that an Aston Martin would win. And the changes were to affect not just a race, but also insure that Aston would still be in the running for a season long championship.

Doug Fehan, program manager at Corvette Racing, had earlier given his approval for IMSA to make some changes to the regulations, all in the interest of competition. What he didn’t expect was the severity of some of those changes. “We want to race and we want to have competition, but we also want it to be fair. What I saw, as far as the changes that we had to endure during the season, was way out of line. I never expected to see us slowed to the extent that they did. It got to the point where our Corvettes were so slow, it took us two laps to pass a GT2 car when we came up on them. They were as fast as we were down the straights.

“When I saw what was happening, the direction that we were headed, I warned the officials that they had better watch out. They were setting a precedent that could bite them in the future.” This prophecy first came true at Salt Lake City, where both Dyson Racing and Intersport were upset about the capabilities of both the Audi R10 diesels and the Porsche P2 class RS Spyders. It was also here in Utah that rumblings about sandbagging were starting to become quite loud. From there, the showdown at Portland occurred, where the behind the scene discussions were likely even more heated than the action on the very warm track.

It seemed that complaints about sandbagging became common throughout the season. At just about any race, you could hear comments that a team was holding back, not wanting to show its true capabilities. It was like people behind the scenes were controlling the pace of their cars out on track. This was true at the front of the field in the P class cars and also in GT1, where many times, it would appear that both Corvette and Aston Martin were accusing the other of holding back, sometimes even in the same session. It also was a common complaint concerning the Penske-entered Porsche P2 Spyders. Take Utah as an example. Here, the Penske cars turned qualifying times that were (relatively) much slower than expected, at least from their practice times, and yet their fastest race lap was within 0.3 seconds of their qualifying times. No other car was able to make a race lap within two seconds of its own qualifying times.

When asked about this, Robinson explained the series philosophy. “We base our decisions (for regulations) on demonstrated performance. What actually occurs on the track. When we are at a track, we have up to 20 timing loops in place. Some are standard, such as pit in and pit out, but the remainder are spread around the track. We also have speed traps where we can monitor the speed capabilities of the cars and we record these for every session. This allows us to compare cars as they performed in the same sessions. But it is not just a single lap time that we are looking at. We also look at entire stints. We note the driver, number of stints on the tires and other pertinent data so that we can evaluate the times and the consistency of those times. With all of the timing loops in place, we can evaluate the aerodynamics, the drag, the tires, the braking, basically all of the components of the cars’ performance. We have three years of data that we can and do pull out to review.”

Unfortunately, as far as sandbagging, no, they do not have a proven way of knowing if or when a team may be sandbagging or even lifting down a straight. But, Robinson is confident that at some point, in the heat of the battle, “the driver will show the true capabilities of the car through sector times. They are not robots. Those drivers want to go as fast as possible, and if indeed, there is sandbagging taking place, it will come out in the data.

“In comparison to the FIA Series, we do things differently," he continued. "They base their decisions on measured and also predicted performance. They use a race simulation program, in which characteristics are entered into the program and then the efficiencies are changed to arrive at predicted lap times. We have chosen not to go that way. Is either way perfect? Probably not, but we are doing what we feel is right. If we make a change in the regulations, we do so for a reason and it is based upon our interpretation of the data.”

While there were issues at the head of the field, the focal point of the controversy this year has been in the GT1 class, where on paper, you have two makes competing against each other with similar layouts of vehicles. It isn’t like a few years ago where the front-engined Corvette was up against the rear-mid engined Saleen S7. Here you had both cars as front-engined machines, outwardly similar.

On the surface, yes, they are similar. But underneath, things are not the same. The DBR9 race car (above) uses the same bonded, extruded aluminum chassis that the DB9 road car uses, with the addition of an integrated steel roll cage, whereas the Corvette C6.R has a steel hydro-formed frame, similar in concept to what is currently used on trucks. In very simple and basic concepts, the two cars are quite different under the skin. To some eyes, the Corvette, owing to its frame design, has more in common with a tube-framed car than with a production based racecar. But that is reality; the Corvette has always been based upon a frame construction. It’s not like they came up with the frame just for racing.

To complicate things though, there are some differences between the production and the race versions that the ACO has allowed. The Corvette Z06, upon which the homologation of the C6.R is based, has an aluminum frame, but Corvette Racing was given a dispensation by the ACO to allow them to race with a steel frame, the same which appears under the standard Corvette. But that is not all, the ACO also allowed the C6.R to race with an alternative head and block design for the powerplant.

Doug Fehan explained the reasons for the dispensations. First the chassis change from aluminum to steel.

“The chassis themselves are identical, except for the material. If they were painted black, you’d never know which one was which. It isn’t that we don’t think the aluminum frame is strong enough. It is, and if things were perfect, we’d be using it. It’s lighter and by using it, we’d be able to get down to 1125kg, even with our redundant starters and batteries, and by doing so, we could distribute our weight better.

"Unfortunately, no proven technology exists to integrate the aluminum frame with a steel roll cage. If a car with an aluminum chassis was to get into an accident, we would have no way of testing it to determine its integrity. If there is any little concern about the safety of the chassis, we will not race it. That is why we went with the steel.”

As far as the dispensations for the engine components, Fehan explained, “the heads themselves are slightly different than production. They have a larger diameter spring seat and they are slightly taller. What we were after was making the heads stiffer, so we could keep the head gaskets working, especially with the higher compression ratios that we are running. As far as the block, comparing our racing version with the production, well, it is identical to the eye. There are no visible differences. What we needed was the ability to tighten up the tolerances, again, for racing applications. It is the same material. We just hand cast them, because when we were pulling them off the production line, we were getting maybe 1 out of 20 meeting our tougher applications. For the block, it’s all a tolerance issue. All of these changes are for the durability. They make no difference as far as power.

“We could use the production parts and get similar power, but it wouldn’t stay together. At this point in the development, a two valve motor is basically an air pump. You can only make so much power out of one. I don’t care if it is a Ford or even a Chrysler. You can only make so much power out of one. Our changes are necessary to make the engine stay together for endurance racing.”

Despite being based on old technology, George Howard-Chappell, Team Manager of Aston Martin Racing, sees the 7-liter pushrod motor as a viable race unit. “The current (2006) ACO and FIA regulations allow a 6% larger restrictor for engines with 2 valve cylinder heads. This rule was introduced a long time ago when engines of this configuration that were being raced had a basic disadvantage due to the restrictions of the road cylinder head and basic architecture of ‘old fashioned’ engines. Of course producing a bespoke racing cylinder head removes this problem and certain competitors have been very clever by doing this and maintaining the 6% power advantage. Perhaps the most interesting confirmation of this was during Petit Le Mans when, with the advantage removed, the Corvette was extremely closely matched to the Aston Martin on Road Atlanta’s long straight. However bickering about this will all be history soon as the FIA, at the request of all the manufacturers, have just agreed to remove the 2-valve adjustment coefficient from their regulations.”

What it all boils down to, in Fehan’s eyes anyway, is that “we are racing a $45,000 (base) vehicle, of which 35,000 units are produced annually, against a high dollar exotic, of which very few examples are produced. Compare the engines. Yes, we have a 7 liter, compared to their 6 liter. But we are running a 2 valve push rod, rocker arm V8 motor against their exotic over head cam V12. The starting point for each vehicle is very different.”

While the pricing may be different, Howard-Chappell stated, “the DB9 is not a specially homologated vehicle for racing as it is truly a production vehicle. By the end of 2006 Aston Martin will have produced over 8,500 DB9s. The DBR9 came to fruition after the DB9 road car had already been engineered and was in production, so the race and road cars were not developed in parallel. This brought with it challenges for the Aston Martin Racing team but when designing the DBR9, Aston Martin Racing stuck rigidly to its philosophy of racing what it builds. This is by far the best way to demonstrate the durability, performance and integrity of its production cars.

“All GT1 competitors are in the business of endurance racing," continued GH-C. "There are two key elements that must be in place to win races – performance and durability. Of course Aston Martin Racing could have opted for waivers to increase the durability of its racecar engine, but in sticking to the regulations and the spirit of GT racing, the DBR9 uses the same block and heads as the DB9 road car. There are three fundamental GT regulations which a GT racecar must carry over from the road car derivative – the basic shape, the chassis, and the cylinder block and heads. The DBR9 ticks all three boxes; this is something that cannot be said for all of the GT1 competitors.”

But why this mess in 2006? All of this was in effect for the 2005 season too, and by the end of that season, the GT1 class was very competitive.

What made 2006 different was effectively two things. First, the ALMS was in a tough situation. The ACEMCO Saleen and the Maserati were gone, as was the Carsport Viper. They needed Aston Martin to run the full season in 2006. Without Aston Martin running a full season, GT1 would be a disaster. All that would be left would be the two Corvettes. Just to complicate matters, Aston Martin Racing brought in much needed funding from Pirelli for the season. Unfortunately, at the time, the Italian tires were no match for Michelin tires. The general perception was that Aston Martin was expecting help to be competitive in the 2006 season.

This was verified by a paper that dailysportscar was supplied by Aston Martin Racing, which stated “Aston Martin Racing entered the 2006 American Le Mans Series (ALMS) on the basis that the series operates a system of performance balancing.”

Howard Chappell sees his team, with the support of Prodrive, as taking on the corporate might of General Motors. As such he is a proponent of performance balancing, which he feels works and is important for the long term health and feasibility of sportscar racing.

Through the years, many series have fallen victim to the economic realities of racing, and eventually someone reaches a level that all but chases off the competition, and many view Corvette Racing, as well as Audi Sport, in that light. Yes, they have the funding necessary to get the job done, but they have also become the best at what they do, and could quite possibly be considered among the all time best that have ever raced. And being the best is not just being the fastest car on the track. It also means they are the best prepared, have the best strategy and also have the best pit crews. It is expertise not just in one area, but in the total team concept.

As a team, anywhere in the racing world today, there may be none better than Corvette Racing. And this made the task for Aston Martin Racing even more difficult. Every little mistake they may have made was amplified, due to the clockwork like performance of the Corvette team. Aston Martin Racing is not a bad team at all, but there were times when some were of the opinion they as a team came up slightly short of the lofty standards that Corvette Racing had established.

Obviously, H-C differed with this opinion. “This may be the view held by some but the Aston Martin crew worked consistently well all season, proving their team work and pit stop ability by getting to the final of the Klein Tools pit crew challenge.”

It was right after Le Mans that IMSA decided to slow the Corvettes. When they did so, it was as if they were penalizing Corvette Racing for being too good as a team. Doug Robinson realizes that this may not be viewed as being fair to a team, especially one as hard working as Corvette Racing. “It is one of the negatives of all of this. We are in effect, making them work harder, as we are affecting their ability to perform.”

But it wasn’t just the Corvette team that was forced to work hard and improve. Aston Martin Racing also improved dramatically as the season progressed. Not just the performance on the track, but in the things that good teams do well – strategy, pit stops, set-ups… You name it. They improved as a team. Unfortunately for them, much of this improvement may go unrecognized. Many will just say it was all of the regulation changes that made Aston Martin Racing a better team. Pirelli too. They improved dramatically. But it will never really be known how much either improved, owing to the way the performance balancing changed, race by race.

Performance balancing, according to Howard-Chappell, when done correctly, works and is critical for the long term success of not just a racing series, but racing in general. He sees balancing as a way of equalizing the playing field, not just on the track, “as it deters large companies from spending excessive amounts on development and testing, because they know that any performance gains will effectively be removed quickly to maintain a balanced grid.”

By incorporating performance balancing, he feels that racing budgets will be better defined and justified, which should encourage other manufacturers to join in. More diverse fields and closer racing will create a more exciting show for the fans and the media, which in turn delivers greater value for all of the shareholders in the sport.

In essence, the ACO and the FIA series have created the first step in performance balancing, by attempting to find a way in which diverse designs of road cars can be translated into equal performing cars on the track. That is already done. That is the starting point of the ACO regulations. But what has been happening in the ALMS is something that they (IMSA/ALMS) feel needs to be done. It looked good in 2005 – not so good in 2006.

At Le Mans, the Aston Martins were running on Michelin tires again. This was just like they did in 2005, and it was here that, according to Fehan, “even though the Astons were running 3% smaller restrictors than standard regulation (incurred for running under the target lap times in 2005), they (the Astons) were still faster, but when we got back to the States and saw we were getting the smaller restrictors, we were both shocked and confused.” So using the accepted ACO regulations, it was actually the Astons that were faster at Le Mans.

But, it must be remembered that the ACO regulations are derived with, in reality, only one race in mind. Le Mans. As a track, Le Mans is unique. It demands a set up that is unique; different than anywhere else. Plus, the tracks in Europe are, in general, a different animal than the tracks in North America, where the ALMS runs. The ACO does recognize this fact, and has granted IMSA/ALMS the right to make competition adjustments, as they see fit. While not a perfect situation, there are many examples that could come to mind which would have benefited competitors and the series if this freedom was granted at an earlier time. The BMW V8s and the Saleen S7R are prime examples of this.

At Lime Rock, the first race after Le Mans, and despite weighing 90 kg more than the Aston Martins, Corvette was right there at the end. Given another lap, possibly only another corner and Johnny O’Connell would likely have gotten by for another Corvette win, but instead it was the Aston Martin/Pirelli partnership taking their first victory, by only 0.03 seconds.

According to Fehan, “everybody thought we were pretty equal at the Lime Rock race, but if Astons hadn’t made a mistake, we’d have been down two laps easy. And then the close finish that was witnessed would never have occurred.” But Howard-Chappell felt that the ‘Vettes had the advantage, with the regs. as they were set at Lime Rock, and then later Portland and Road America, the latter two which were won by Corvettes. According to GH-C, it was at the Lime Rock race that the faster No. 4 Corvette was involved in an accident with a prototype and the 009 car benefited from a lucky pit call, entering the pits just in time to gain a lap under the safety car, to win by a fraction of a second.

Then came Utah (Tomas Enge and GH-C all smiles, right), where the ‘Vettes were even further slowed. Oliver Gavin reported the mandated new restrictor “makes me feel like I’m driving an F3 car.” It was at this point that the grumbling by the team members started. Nothing “official” was stated, but when the opportunity was given, comments about weight and restrictors were tossed in, as if people needed to be reminded.

It was at here at Salt Lake City, just when the season was hitting its peak, that things turned really ugly. While nothing was officially said, there were rumors flying that Aston Martin Racing may not last the season and may go directly home.

When the teams arrived at Portland, one week later, yet more controversy greeted them. It seems that Fehan pointed out to the officials that IMSA regulations (6-01) state that they “may not issue notice of an additional change to any given parameter without an intervening race having occurred.” This was in reference to the regulation announcement made before Lime Rock, which saw one batch of regulations for that race, and then another for the remaining races. Thus, it was back to the Lime Rock settings.

But Portland greeted the teams with high heat yet again, as well as a track that never could be confused for being high in grip. Before the race at Portland, GH-C stated, "this backs up what we thought, which is that the circuit at Salt Lake was particularly well suited to the car and the Pirellis. It will be a real struggle here. There has been a lot of reaction from our competitors regarding the handicapping process. But with three wins to Corvette and two wins to Aston Martin so far this season it would appear that IMSA has done a great job of balancing performance in the GT1 class which is, after all, a handicapped formula.”

Obviously, and not surprisingly, Howard-Chappell saw things differently than Fehan, when it came to the performance capabilities of the cars. Where one saw a change, he saw it as the other team getting an advantage. H-C, after the season had wrapped up - “Although the C6.R and DBR9 were becoming very evenly matched, a further series of performance adjustments were made in favor of the C6.R, which duly dominated the next two races at Portland and Road America. Further adjustments were made to both cars, but slightly favoring Aston Martin, for the next race at Mosport, which the DBR9 won.” Whereas Fehan would state that he felt the Astons were very close, pace wise, at both Portland and Road America. Both sides were sending conflicting messages, claiming the other was sandbagging or had the advantage.

Petit Le Mans was yet further confusion. In what was expected to be an intense qualifying session, the Aston Martin team opted to not push it, preferring to save the tires for the race. Early in the race, a pace car intervention dropped the 'Vettes a lap back, and although the pace was hot, it appeared the Aston Martins had an advantage, and it was an Aston Martin 1-2 when the race ended. A late stop for the Corvettes for brake service confused some at the time, as no problems had been seen previously.

Fehan explained: “We went after a different strategy. We knew we were not going to be as fast as the Astons, so we were just hoping to stay on the lead lap early and then see what happens. We knew we wouldn’t have the pace to race with them. So we looked at our situation and decided that the best place for us to gain was in braking. We opted for a very aggressive strategy on the brakes, but it didn’t work out. The only way we were able to stay as close as we were was due to the aggressive strategy we adapted. But we wore out the pads. Jan didn’t notice anything, because with carbon brakes, there is no indication of them going away. There is no change in performance, at least until they wear out and they explode.”

At Laguna Seca, it was more of the same, although this time, it appeared that the regs. had finally been sorted out and the two makes seemed to be as close as they had been all season long. At the end of the race, it was the #3 'Vette running out of tires, trying to chase down the leading Aston. When it was apparent that the #3 'Vette was out of the running, it was too late for the #4 have a run. Team strategy, which had hoped to see the #3 finish strongly and thus finish second in the points, didn’t work out. When the season all ended, it was evenly split, five wins apiece. The last race indicated something that was close to equality, and the final season results did the same, but those involved or watching consistently knew better.

It was Fehan who might have had the final word on the subject at Laguna. “We’ve been here since 1999, and we have always raced straight up. But not this year. It was not straight up at all… I do have to say that lost in all of this was that Pirelli did an amazing job developing their tires for the Astons. Their huge advances were overshadowed by all of the regulation changes. If we are to come back, and they are too (Aston Martin), I would like to be able to go at it straight up, as per the ACO regulations.”

He continued, “I do think that if we were to leave the series, you’d see about 20 cars show up in the GT1 class next year.” That remains to be seen, but there has always been a thought that the likes of Corvette Racing and Audi Sport have in the past scared away some of the possible competition.

While the competition did not scare off Aston Martin, Howard-Chappell is also of the opinion that he would like to see the regulations settled. He is concerned that how things went this last season added to confusion among the teams, the media and the fans. He feels that unless the issues are resolved, the continued use of performance balancing will amplify the very instability that it seeks to address.

To address that, George Howard-Chappell would like to see the series further clarify the basis that the series uses to arrive at its adjustments. In his opinion, “decisions regarding performance adjustments are being made based on the interpretations of data supplied by the teams themselves, together with regular circuit timing data. The basis upon which performance adjustments are being made is not immediately apparent and is not published. Even if the exact results of the analysis are not shared with the teams, they should be advised on the precise criteria upon which the decisions are being made. I feel our principles and views on performance balancing are reasonable and fair. In the 2006 FIA GT Championship, Aston Martin customer teams have won only two races, yet we completely support the way in which the balance of performance measures have been applied – with transparency and objectivity. This is in contrast to the ALMS where Aston Martin Racing won half of the races but does not feel that there has been a full and transparent explanation of the basis upon which performance balancing decisions were made.”

He also suggested that using a regulation in-car data system “would go a long way to improving the science and objectivity behind performance adjustments.” At Laguna Seca, Doug Robinson stated that they had been testing such a unit during the season. “We’ve used it in various cars for several events already. It’s battery powered and GPS based. We’ll provide mounting brackets for all of the cars and will incorporate it into use next season.”

Unfortunately, the way the 2006 season turned out, it appears that there were no winners. As a series, the ALMS looked bad because of the way the regulation changes were doled out, the way the competitors reacted and the way that the complaints escalated. The public bitching by the teams at every opportunity got to be tiring and really took away from the action on the track. Is that any way to attract new partners? No, but as earlier stated, changes were deemed necessary in order to keep GT1 a viable proposition for 2006.

In the end, for Aston Martin and Pirelli, recognition of a job well done will forever be obscured or distorted because of the controversy surrounding the changing regulations. And Corvette? While they may have won some public support and sympathy, they left the season with a poor taste in their mouths, even though they won the Manufacturer, Driver and Tire championships. IMSA came close many times to getting the regs. right, or at least close to right, but then something changed. Maybe it was development of the cars. Maybe it was the development of the tires. Maybe it was simply improvement as a team.

So where does this leave everybody, now that the season is over? Fehan had earlier stated, “If we can’t find a forum to race here (in the ALMS) that is consistent with our mission statement, which is to showcase the durability, reliability and performance of the Corvette, we need to go somewhere where we can.” He continued to explain that unless there is a firm plan by the ALMS to return to the ACO based regulations, upon which the Corvette C6.R was homologated, expect to see the team racing elsewhere in 2007. Aston Martin is rumored to be returning with a different tire manufacturer and IMSA has stated that there will be more consistency in the regulations in the future. No longer will there be weekly changes in the regulations. Doug Robinson verified that “the regulations will be reviewed during the season and our intention is to make adjustments one third and two thirds of the way through the season. Our intention is to let them race, but if we see a trend that one team is dominant, then something has to be taken away. We will support the FIA/ACO regulations, but we will also adjust as needed. We do have the approval of the ACO to make adjustments to our regulations before the season starts. And that is not just in GT1 either.”

At this point, it is too early to tell exactly. Corvette hasn’t yet announced its intentions for 2007. They are awaiting word from IMSA/ALMS on future regulations, but also have other plans in place, just in case they don’t come back. But even starting with the ACO regulations may not be enough to bring them back. Fehan is still concerned about the possible adjustments that will occur during the year and to what extent they may be adjusted. “What’s to prevent them from making changes similar to what we were forced to run with at Salt Lake City?”

In some ways, it makes perfect sense for Corvette Racing to leave the ALMS. What else have they got left to accomplish in the series? It would be a shame to see them leave the series that they have been very instrumental in helping to build, but something tells me that the thought of Corvette Racing, as an American Team, going over to Europe to kick some a$$ has some appeal to Fehan.

It is evident that IMSA has learned something from 2006, as the policies they have in line for 2007 appear to be a step in the right direction. At times, things were close to being good, but the constant changes just never allowed us to feel that way, especially with the comments that were made public. For 2007, a perfect world would see both Fehan and Howard-Chappell get their wish and find a common ground upon which to compete in the ALMS again, and see the GT1 class return to the promise that it showed at the end of the 2005 season, and without the bickering. Stay tuned…