The Ferrari 499P Le Mans Hypercar will race at a minimum weight of 1041kg, 34kg below the figure at which it competed in the WEC curtain-raiser in Qatar last month, and has had maximum power raised by 7kW (9bhp).
Toyota’s GR010 HYBRID LMH has lost 29kg and gained 6kW in the table issued by the FIA WEC Committee.
All nine models competing in the Hypercar class of the WEC will be lighter and run more power power in Sunday’s Imola 6 Hours than in the Qatar 1812Km on 2 March with the exception of the rehomologated Peugeot 9X8 LMH.
The Porsche 963 LMDh that blocked out the podium positions in Qatar has a minimum weight reduced by 15kg and also a power increase of 3kW.
The third biggest weight reduction is for the Alpine A424 LMDh on 28kg, closely followed by Isotta Fraschini Tipo 6 Competizioni LMH and the BMW M Hybrid LMDh on 27kg and 25kg respectively.
Cadillac has received the smallest reduction in weight, a 2kg drop to bring it down to the 1030kg class minimum.
But its V-Series LMDh has been given the biggest increase in power with a 18kW (24bhp) addition.
The heavily-revised Peugeot, now known as the 9X8 2024, will race at 1061kg, 31kg above the weight of the old car at Qatar, and at 510kW maximum power rather than 520kW (683bhp compared with 697bhp).
The deployment speed of the front-axle hybrid system for the Peugeot is now 190km/h, the same as for the other LMHs.
This follows the French manufacturer's switch to 29cm-wide front tyres and 34cm rears from the 31cm all-round of the original version of the 9X8.
No explanation, as is normal on the publication of the BoP table before each WEC race, has been given for the changes.
The across-the-board weight reductions and power increases are likely the result of the differing track characteristics of the Autodromo Internationale Enzo e Dino Ferrari at Imola and Qatar’s Losail International Circuit.
Introduction of the so-called “power gain” component of the BoP, devised to level the speeds of the Hypercars in a straightline, has been delayed.
A plus or minus figure will be applied to the maximum power of each car above 210km/h (130mph) to more accurately match their acceleration and top speeds.
Power gain was trialled by some manufacturers during the pre-Qatar Prologue test.
The Imola BoP table for the new-for-2024 LMGT3 has also been published.
Aston Martin faces the biggest change on its pair of evolution Vantage GT3s.
Minimum weight of the car that finished second and third in Qatar has been reduced by 12kg, but it has received a power hit.
Manufacturers declare a power curve on the homologation of the car and a further 14 curves, with power reduced in one percent increments, are then set.
The Aston will race at wthe lowest possible power, listed in the table as P15, in Italy.
Power gain above 200km/h (124mph) is already in force in LMGT3.