The aerodynamic changes made to the BR Engineering LMP1 car in the wake of its aerial accident at the Spa FIA World Endurance Championship opener have been revealed by chassis builder Dallara.
The BRE BR1s run by the works SMP Racing squad and the customer DragonSpeed team were fitted with larger front wheelarch openings ahead of the Le Mans test day on Sunday.
These openings, which were originally slatted vents, prevent a build-up of air pressure under the nose and have been a key weapon in attempts to stop LMP machinery taking off since 2001.
The trio of BR1s will also run more drag and downforce than originally intended for the Le Mans 24 Hours on June 16/17, while the centre of aerodynamic pressure has been shifted forwards by the changes.
Luca Pignacca, head of Dallara's technical office, told Motorsport.com: "We will now have bigger openings in the front bodywork and we will abandon the more extreme downforce configuration we were planning to run.
"We will have more downforce than planned, which unfortunately means we will lose some performance here at Le Mans."
The revisions are the result of the accident in which the SMP BR1 driven by Matevos Isaakyan backflipped at Eau Rouge in the closing stages of the Spa WEC round early last month.
Russian entrant SMP and sister organisation BRE vowed in the wake of the shunt to make whatever changes were necessary to prevent a recurrence of the accident at Le Mans.
A number of factors are believed to have caused the incident.
Isaakyan, who shares the #17 SMP entry with Egor Orudzhev and Stephane Sarrazin, was following in the tow of a Toyota TS050 Hybrid and also hit the right-hand kerb in the middle of Eau Rouge.
The car had just pitted after Isaakyan had sustained a puncture after running wide at Blanchimont.
Because only one tyre was changed there was little or no time to clear the internal front aerodynamic surfaces of spent rubber or marbles, something which is standard procedure on LMP machinery.
The WEC rule makers, the FIA and the Automobile Club de l'Ouest, have requested more data from LMP1 entrants following the Isaakyan's accident.
Teams will have to open up more telemetry channels to allow race officials to monitor downforce loads in real time, as well as providing additional data every two hours through the test day.
The customer DragonSpeed BR1, which is powered by the Gibson normally-aspirated V8 rather then the AER turbo V6, will run for the first time on Sunday after being built up around a new monocoque.
The new tub was required after Pietro Fittipaldi crashed heavily at Eau Rouge during qualifying, breaking his lower left leg and his right ankle.
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