The Balance of Performance (BoP) for the DTM season opener at Spielberg was only communicated to teams on Wednesday evening, significantly later than the usual one-week lead time, underlining the scale of the challenge faced this year.
The late arrival comes as no surprise given the complexity of the process. A key factor is the new exclusive DTM tyre from Pirelli, introduced this season and finalised relatively late, which has altered the competitive order. As a result, data from other racing series has offered limited guidance for BoP provider SRO Motorsports Group.
Further complicating matters, a planned qualifying simulation during the official DTM test in Spielberg, intended to generate crucial reference data with new tyres and fixed fuel loads, was cancelled due to rain, leaving a significant gap in the data set.
Manufacturers asked to provide additional data
In response, BoP officials requested “run sheets” from manufacturers for the first time, detailing set-up changes, lap times and test programmes from the Spielberg test. However, the accuracy of such data remains open to question given the inherent competitive interests in securing a favourable BoP.
The task was made even more complex by changes to the grid. The arrival of the new Lamborghini Temerario GT3 introduces an unknown variable, while updated Evo versions from Porsche, Ferrari and Ford also shift the baseline compared to last season. In addition, the BMW now features a revised turbo configuration, requiring a fresh assessment.
Spielberg remains a unique BoP challenge
The characteristics of the Red Bull Ring further add to the difficulty. Situated at nearly 700 metres above sea level, the circuit has historically posed challenges for BoP calculations.
Naturally-aspirated engines lose 15hp to 20hp compared to turbocharged cars relative to lower-altitude circuits, requiring constant monitoring of ambient pressure and corresponding turbo adjustments. With temperature expected to range from 5C to 24C over the race weekend, this fluctuation will also play a role, as turbo engines tend to perform better in cooler conditions.
With only eight significant corners and several long straights, any imbalance in engine performance is amplified at Spielberg.
Mercedes could benefit from the conditions
Among the baseline classifications, the Mercedes-AMG GT3 retains its 36mm restrictor and favourable lambda value of 0.91, along with a relatively low weight of 1,325kg.
The new DTM tyre is expected to suit the car better, as it reaches operating temperature more quickly than its predecessor – an area where the Mercedes struggled at Spielberg last year. The relatively mild temperature forecast could also play in its favour.
The McLaren 720S GT3 Evo, which set the pace in testing with Ben Dorr, remains unchanged and effectively serves as the reference point. Meanwhile, the updated Porsche 911 GT3 R Evo retains its 41.5mm restrictor, matching the specification used by its predecessor.
| Aston Martin | 1,330 kg | 1.37 – 1.98 bar | +0.0 to +0.2 bar | 53 / 53 / 50 mm | 6° | 0.91 |
| Ferrari | 1,335 kg | 1.0 – 2.46 bar | +0.0 to +0.06 bar | 80 / 83 / 50 mm | 3° | 0.90 |
| Ford | 1,320 kg | 2 × 35 mm | -15 kg / -1 mm | 84 / 92 / 40 mm | 8° | 0.88 |
| Lamborghini | 1,335 kg | 1.2 – 1.7 bar | +0.0 to +0.12 bar | 65 / 70 / 50 mm (-15 / -15 / 0 mm) | 5° | 0.90 |
| McLaren | 1,310 kg | 1.1 – 1.79 bar | — | 65 / 70 / 50 mm | 6° | 0.88 |
| Mercedes | 1,325 kg | 2 × 36 mm | — | 81 / 87 / 40 mm | 6° | 0.91 |
| Porsche | 1,310 kg | 2 × 41.5 mm | — | 101 / 120 / 50 mm | 7° | 0.89 |
| BMW | 1,340 kg | 1.0 – 2.39 bar | -0.06 to +0.06 bar | 82.5 / 81.5 / 50 mm | 4° | 0.90 |
Adjustments aimed at boosting Lamborghini and BMW
Efforts to bring the Lamborghini Temerario GT3 up to speed are evident in the BoP adjustments. Compared to the test, the car has received up to 0.12bar more boost pressure at low revs, along with increases in the mid-to-high range. It is also permitted to run 0.15mm lower at both front and rear, improving aerodynamic performance in corners.
The BMW M4 GT3 Evo, now equipped with a production-derived turbo, sees an increase in boost pressure of up to 0.06bar in the mid-range, addressing issues encountered during testing where tyre graining contributed to a lack of pace.
Similar measures have been applied to other turbocharged cars. The Ferrari 296 GT3 receives a 0.03bar to 0.06bar increase across much of the rev range, while the Aston Martin Vantage GT3 gains a significant 0.2bar increase at low revs.
Special provisions for Ford Mustang
The Ford Mustang GT3 benefits from a special exemption regarding ground clearance. While regulations mandate a minimum of 50mm for cars homologated from 2022 onwards, the Mustang is allowed to run at 40mm, generating additional downforce without relying solely on engine performance.
At the same time, its restrictor has been reduced by 1mm to 35mm, compared to 38mm last year, balancing its straightline potential on a circuit where it is traditionally strong.
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