IWSC: Major Balance of Performance Changes Will Influence Rolex 24 Outcome

Photo Credit: IMSA

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We all knew it was coming. Almost two weeks after the conclusion of the preseason Roar Before the Rolex 24 open tests at the Daytona International Speedway, the governing body for the IMSA WeatherTech SportsCar Championship has revealed its first list of Balance of Performance adjustments, which will be mandated for the first day of on track action on Thursday, January 28th. As always there were winners and losers, and while no teams or manufacturers were necessarily eliminated from overall or class victory contention, the task for some has certainly become a much taller one.

For those of you new to IMSA sports car racing, the BoP adjustments are used as a means to keep as level a playing field as possible and to encourage competition to where no one team or manufacturer will dominate the season. This factor was a common issue with the former American Le Mans Series when in the presence of Audi during the 2000s decade and by Honda in the final years prior to the sport’s unification in 2014. While not always the most popular thing to deal with in the eyes of teams, drivers, and fans, they always have thrown a curveball or two into the equation, as they appeared to do so on Thursday. So with that intro out of the way here by class is what has been done and how I think it will influence the final results on January 31st.


After going 1-2 on the overall speed chart, the Honda-powered Ligier JS P2 coupes run by Michael Shank Racing and Tequila Patron ESM respectively were the most affected Prototype in relation to the BoP. The cars will have to run with an extra 10 kilograms of ballast tacked on to their minimum weight, plus the turbo V-6 engine power plant’s muscle will be reduced at varying RPM levels.

The two surprises during the test: SpeedSource Mazda Racing and DeltaWing Racing Cars were also tagged likewise. The Lola-Mazda coupe, which now features a gasoline-fueled V-6 turbo power plant as opposed to the SkyActiv-diesel engine used in 2014 and 2015, will also suffer a reduction in boost power, while the DeltaWing DWC13 coupe’s Elan engine will also be tagged with a reduction in power, plus an extra five kilograms of ballast for the car itself.

Obviously, the power advantage that the LMP-2 eligible cars had over the Daytona Prototype-styled cars will be reduced, while the extra weight will make those challengers less nimble in the infield road course section and the bus stop chicane on the Daytona Superstretch. While the pace over a single lap has been comprised, the question with these entries is still largely focused on reliability, the main cause for their inability to win races in 2015 endurance events.

Interestingly, the only LMP-2 car to avoid getting hammered by the BoP was the SMP Racing BR01 with Nissan V-6 power. While outright pace was not affected on paper, the peeling off of 10 kg could prove useful in terms of over the course of a single lap.

As for the Daytona Prototypes, the four Chevrolet Corvette DPs saw no adjustments in this set of BoP changes, while defending champions Chip Ganassi Racing will be forced to run with less turbo boost from their twin-turbo V-6 Ford EcoBoost engine, but without weight adjustments to their Riley DP. In attempt to make the Dinan-BMW Riley from Fifty Plus Racing more competitive, the team has been granted a two millimeter larger air restrictor for their V-8 based engine.


The changes do not influence my previous thinking that two-time defending IMSA Prototype champions Action Express Racing are the team to beat in the Rolex 24 at Daytona next weekend. I still expect the LMP-2 based entries to control the proceedings in qualifying, but as the race gets going look for the Corvettes and Chip Ganassi’s Ford-Riley to start taking over as night begins to fall on Saturday.

While the results of the BoP are not a fatal blow to teams such as the Ligier runners from MSR and ESM, the news certainly was not welcome. How the teams and their drivers rise to the challenge could greatly influence how they fare in the race itself, in addition to the durability question I raised earlier.


In the grand touring ranks where the BoP changes have spurred on the most controversy over the past two seasons, the changes were a plenty in the professional driver, mainly factory-backed upper GT Le Mans division. The IMSA officials were quick to lock down on the new twin-turbo V-8 engine in the BMW Team Rahal M6 GTLM. Boost ratios have been lowered, while the car may also suffer from greater drag on the Daytona tri-oval sections of the circuit. The car will be required to run a 10 millimeter larger Gurney flap on the rear wing (from 5 mm at the Roar test, to a 15 mm one during race week).

Corvette Racing’s heavily upgraded for 2016 C7.R was hit with a minor restriction on its supercharged V-8 engine air opening. while the new Ford GT for Chip Ganassi Racing and the three Ferrari 488 GTE runners will also suffer from reductions in boost output.

Only the Porsche 911 RSR, another major upgraded car from 2015 entry by Porsche North America was not tagged with any major performance hamperments.


You can pretty much throw out all of the timing reports from the Roar tests. It is safe to say that Porsche North America will not be on the bottom of the charts as they were during the Roar and should again be a major threat for the top step of the podium, riding the momentum of a near perfect second half of the 2015 campaign.

The changes on the BMW, Corvette, Ford, or Ferrari challengers I do not think are significant enough to put anyone in danger of being locked to the bottom of the performance charts. As in Prototype, the question of durability will more outweigh the tweaks seen here, although that may change when the sprint race portion of the 2016 IMSA WeatherTech Championship begins at Long Beach.

As for the favorites, nothing really changes here either. Porsche North America on the strength of its second half dominance and Corvette Racing on their wins at Daytona, Sebring, and Le Mans remain as the most likely victory candidates entering next week.


Despite the fact that Alex Job Racing’s Leh Keen set the fastest lap in the division at the Roar test just under two weeks ago, the new Porsche GT3-R also will remain unaffected by the latest BoP updates. The other two brand new challengers for 2016 however, were not as fortunate.

The new for 2016 Audi R8 LMS will be 20 kilograms heavier during race week and will feature a reduction on the air opening for its V-10 engine by a full two millimeters. Last year’s Audi R8, which Flying Lizard-Krohn Racing will enter at the Rolex 24, will run with 10 fewer kgs in weight and a larger air opening, possibly putting it on closer to equal footing when compared to the new car.

The Lamborghini Huracan GT3, which controlled the time charts prior to Keen’s effort on the final day, were also tagged hard by IMSA. The Italian marque will also carry an extra 20 kgs and like the Audi will run a 2 mm smaller air opening to the engine.

Along with Porsche, Riley Motorsports’ Dodge Viper GT3-R will also benefit from the BoP changes. The monster will run with 20 kgs less weight and despite a one millimeter smaller air opening to its eight liter, V-10 engine, the challenger could once again regain the outright pace advantage on Daytona’s tri-oval section of the course, which it enjoyed when Riley won the GTD division at the Rolex 24 last year.

Ferrari and Aston Martin, who also were largely off the pace of the Lamborghinis and Porsche at the Roar, will each run with less weight during race week, with Aston Martin also getting more air to its V-12 engine. While Ferrari does not see a change in the air restrictor for its 458 model, the V-8 engine’s maximum RPM output will be cut by 200 RPMs for Daytona.

Despite also not being among the top runners at the Roar, Turner Motorsport’s new BMW M6 was also penalized heavily by IMSA. The new entry will feature 10 extra kgs in weight, whilst also suffering a drop in boost pressure, probably the most crushing blow among any of the classes for this set of Balance of Performance adjustments.


The finesse factor that I felt Riley Motorsports would need to defend its title in the GTD division at Daytona may no longer be necessary. If the top end pace gap is similar to last year, only the Porsche may be able to match the Dodge Viper approaching the entry to the infield section of the course.

The hopes of Stevenson Motorsports and Magnus Racing in the Audi camp have been altered towaqrd the negative, but not to the point where their chances are cancelled out.

Beyond that, the other contenders could be in over their head based on both the previous timing outputs at the Roar, topped off by these performance changes.


Although on paper, the changes would at first glance seem to make one think that the complexion of next week’s Rolex 24 at Daytona has changed greatly. In reality and in my opinion however, the complexion of the race has largely been unaffected by these changes and if anything the action in some cases could even get more exciting as the race proceeds in its twice around the clock fashion.

Stay tuned to OnPitRoad.com for further IMSA sports car commentary from Matt Embury.