So I did the calculations for the P1 and the LaFerrari too.

The LaFerrari's 6.3L V12 ended up at 115.6HP/L while the P1 only getting 86HP/L, and it was converted to the equivalent of a 9 liter NA engine. P1 runs a 8.1:1 compression and 1.4bar of boost.

For comparison, the 991.2 Turbo S, at 3.6L and 580HP, converts to a 7.8L flat 6 and resulting in 74.8HP/L

Aaron, a boosted engine will never have the 'efficiency' of a NA engine. It's only efficient on paper because of the smaller capacity and at government test cycles they ran the off boost map, that combines with a low compression ratio makes the engine drinks a lot less fuel than they really are when testing.

But this video shows you that a boosted engine is actually cheating, at full power output, they eat fuel like a much bigger engine. The P1's 3.8L V8 is actually drinking fuel like a 9L V8 at full power. (the fuel consumption part is pretty linear with the amount of air going in. so one can safely interchange)

 

 


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