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WEC/IMSA: Technical Regulations Confirmed for LMDh Category

As we build up to the 24 Hours of Le mans, the technical regulations for next year's LMDh class have been finalised and released.
  • The Le Mans Daytona h (LMDh) prototypes class is set to replace the Datyona Prototype International (DPi) class.
  • They will race alongside LMH category in the FIA World Endurance Championship from 2021.
  • The confirmed regulations are a product of the joint effort from the FIA, IMSA and the ACO.
Back in January, during the build up to this year's 24 Hours of Daytona, ACO and IMSA announced that a new LMDh class would replace the DPi class from 2021. Eight months on, with the details finalised, the technical regulations have been confirmed ahead of this weekend's 24 Hours of Le Mans.

Presidents of IMSA, the ACO and the FIA's Endurance Commission shared the job of releasing the news at a press conference on Friday:

"Since the announcement of the IMSA and ACO convergence back at Daytona in January, and the opportunity for a competitor to enter the same car at both the IMSA WeatherTech SportsCar Championship and the FIA World Endurance Championship, we have received and responded to many specific questions from prestigious automakers.
"We’ve also had those same automakers very involved in the development of the LMDh regulations, and I think all of us are very encouraged and confident, that as we announce the final regulations today, it will bring more names to the table.
"Certainly, the top level of endurance sports car racing has now a very clear, tangible and very bright future. This is, quite frankly, very good news in this difficult global context."

IMSA and ACO technical directors Matt Kurdock and Thierry Bouvet shared some of the main points of interest for the new LMDh class, which will feature hybrid engine technology, with cars costing one million Euro without the power unit.


Authorisation has been given to just four chassis constructors to manufacture LMDh cars, including Dallara, Ligier, ORECA and Multimatic. The minimum weight for the prototypes will be 1,030kg, with a common wheelbase length for all cars. Each manufactuer will be allowed "to bring their own identity and styling cues" with free reign of the upper body styling, while using a "controlled underfloor."

The hybrid powertrain will be a product of Williams Advanced Engineering, Bosch and Xtrac. The combined power output from the internal combustion engine and a "spec hybrid powertrain system" will be just over 670bhp:

"The Bosch motor is integrated with the Xtrac gearbox, while the Williams Advanced Engineering battery will be integrated with the Bosch motor controller. This is all in a compact assembly, which installs from underneath the survival cell in an isolated compartment from the driver.

Kurdock described the collaboration between IMSA and the ACO as being "effective":

"ACO and IMSA have led a collaborative effort along with the four chassis constructors and the three hybrid powertrain suppliers to come up with a common LMDh solution.
"I think this demonstrates effective work and collaboration between ACO and IMSA...we should have announced this in June had we not had the health crisis.
"I think the efficiency of the process is a further reflection of the importance of this collaboration between IMSA and the ACO, and the future of endurance sports car racing...To have the same car be able to run at Daytona and Le Mans is an expectation of all of our manufacturer partners, and can you only imagine how this is going to make our fans feel?"

Let us know what you think of the new regulations, and who you hope to see lining up next year in the LMDh category.

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Dirk Steffen

Porsche Factory Jackass™
I am not sure if we have the same understanding of a spec series. Personaly, I couldn't care less at this point how super innovative the cars are, because I care for great racing, that the cars look good and that they sound great. I think, it's time that we move on from the idea that everything has to be super innovative and diverse, because the costs for racing have increased so much that there won't be any high class racing if we keep going like that. Best example being the recent decline of DTM. The times that Porsche sold their 956s or 962s to some private teams are long gone. It is essentialy what those mentioned chasis manufacturers do these days. And as far as I understood the concept, those mentioned manufacturers aren't set in stone and it could very well be that we see more of them buidling their own LMDh chasis in the future, while the engineers will still have alot of room to find some clever solutions.

Innovation in racing has always been indeed one of the major driving forces behind manufacturers willing to spend immensely costly budgets on racing programs (next to the obvious marketing effect successful racing programs create).

Taking the unique manufacturer made racing machines and replacing them with generic tins labeled as such takes the marketing effect away and a frozen spec series as currently suggested eliminates the entire innovation vector of going to race in the first place.

Personally I have never been interested in any of the re-label exercises currently in fashion, be it Alfa Romeo labeled F1 cars, Ford or Mazda branded Bathurst racing spec cars,the current crop of Indy cars, ... even the current LMP2 machines although they made for great racing moments have zero impact on me.

I do need a manufacturer or a privateer team to come up with a design, build it and race it but then I am old fashioned I guess.

One very major reason for the demise of the DTM series is not necessarily cost explosion but the major factors have always been that manufacturers who left the series had either costly other commitments in racing programs and simply had to decide cost benefit factors which budgetary commitments net the most potential - why would BMW and Audi keep showing race cars on weekends to an almost exclusive German fan community and try to sell a combined ~1/2 Mio cars more on the German market when without even spending money on a racing program they can focus on much more lucrative markets and sell many more cars.

The DTM too was a racing series constrained by regulations that forbade in essence any technology transfer from the race track to the production cars. Where hybrid and electric vehicles are in the intermediate future of production cars to market learning something useful from running V8 spec engines is hardly the case.

You have got the manufacturer handing down their racing cars to privateers quite wrong.
Now more then ever is this in fact a major part of the calculation in race car programs - look no further than the WEC - ALL privateer GT cars are actual handed down vehicles from the manufacturers previous years ran cars by design of the regulations and by design of the business model of the manufacturers.

This is a good thing - without this the costly development of cutting edge GTE cars would be so much more costly for the manufacturers and the grids would be quite empty without those privateer teams running 1 or 2 year old cars previously ran by the works teams.

The proposed LMDh regs do not seem to take any account of this.

It is a lose lose.

The fans lose to see unique true manufacturer made cars (no more Ferrari, Porsche, Aston Martin, ....) but instead we get to see generic tin cans with manufacturer stickers.

The manufacturers lose all credibility as their former unique identities get washed down the drain of a relabeling and marketing culture.
Who will pursue in the future to ever drive a Porsche or Ferrari one day if all the race cars labelled as such are just Hyundais anyway?

I am not looking forward to watch this one bit :-(

The alteration of the generic LMDh cars as currently proposed sees in fact very little room for unique manufacturer changes.
No manufacturer designed chassis are permitted instead only a handful of "standard chassis manufacturers" are planned to be licensed to build ALL chassis to spec, cosmetic alterations in limits permitted to allow for re-branding.

All I read in the blurbs is simply all bad.

Davy Jones

"Daytona h (LMDh) prototypes class is set to replace the Datyona"

Isn't Datyona a circuit somewhere in Asia? :D
One day there will be hybrid/electric-drivesystems in Nascar too...
Honestly i think hybrid technology is pretty cool it gives the driver more tactical options than a conventional engine would if it is used wisely you wouldent need to refuel for a whole trip ontop of it you still get the cool sounds of a conventional engine as well you dont get that with a electric car so if i were to chose which vheical i'd buy i'd go for a hybrid plus you dont need to store mass amounts harmful battery acid which could also harm the environment during the manufacturing process.
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