[Graham Goodwin]

Originally Posted by canaglia

Sorry, but no, ESM and MSR ligier-HPD that ran in IMSA 2016 used the HPD 3.5L V6 turbo, an enlarged version of the 2.8L engine used in ACO lmp2, the same engine later used in acura dpi. Both are enlarged and racing tuned version of an old unit used in cars like honda accord iirc.
That 3.5L engine was used only in IMSA because it wasn't allowed in ACO WEC/ELMS/LM where the only engines allowed were the nissan-zytek 4.5L V8, the bwm-judd 3.6L V8 and the HPD 2.8L V6 turbo.
ACO nissan/bmw/HPD powered lmp2 were in the range of 500-520hp, the ESM/MSR ligier-HPD were by bop in the same dp range of 550-560hp, that's why that car wax extremely competitive during 2016 IMSA and it isn't comparable to ACO lmp2 cars.
Unlike BR01 data that is not so easy to discover around, you can fact-check the IMSA ligier-HPD in a couple of minute.

You're writing nothing new... dome, zytek, wirth and many others revealed lmp1 and lmp2 coupè projects in early-mid 10's but none of them managed to see the sunlight. I usually don't comment things I don't know, and of course ACO made the 4 manufacturers rule to make lmp2 class more somehow standardized, cost controlled and overall better organized. I just find unlikely they made that because they were scared by failure private projects like dome-strakka, kind of cars that ACO couldn't however prevent to run in lmp1 if they were made with homologable chassis since there have been lmp2 with lmp1 specs chassis before 2017 like oreca05, adess lmp2 and br01.
Don't get me wrong, I'm not saying you're wrong about this, it's I just can't give a better opinion.

Ref the LMP1 point - read the Strakka article linked - it makes it clear that the economies of scale accelerated away from affordability

Ref the motivations - try this for size - when the new proposals for 2017 were published the ACO called a meeting to discuss them with teams - Neither Strakka nor SMP were invited