Ferrari "kerb weight" (with or without petrol?)

Is Ferrari SpA "kerb weight" quoted with or without fuel/gas/petrol??

It was always my understanding that Ferrari's "kerb weight" was with all fluids, including gas (petrol), and that Ferrari's "dry weight" was without any fluids, including engine oil and tranny oil and diff oil, etc.

HOWEVER, I have often wondered if the difference between Ferrari's marketing "kerb weight" and the "curb weight" in our US owners' manuals is actually the inclusion or exclusion of gas/petrol.

At 6.2 lbs/gallon in a 25 gallon tank, that's 155 lbs, which is almost precisely the difference in weight between the US Users Manual's "curb weight" and the Euro Users Manual's "kerb weight" for the Stradale. (That weight difference has never really been explained well... see this thread).

In general, Ferrari quoted weights are considered "optimistic"; but you'd think they'd get "caught" at giving bogus weights... it is easy to check. But perhaps Ferrari quoted weights are rather misunderstood... 100-150 lbs of petrol/gas would explain most such "optimism".

So, I've been wondering that for a while... when out comes the recent F430 Challenge announcement, which says:

That seems to define "kerb weight" WITHOUT petrol. However, it could be argued that they were rather telling you that this is not a normal "kerb weight", but rather a strange "kerb weight without petrol". Well, to figure that out, let's look at other "kerb weights"...

The F430's kerb weight is 1450kg (3196lbs). The F430 Challenge kerb weight is 1225kg (2695lbs). If the former is with petrol and the latter without, then the weight difference is just 155kg (347lbs) rather than 225kg (501lbs). The former is not all that impressive.

In contrast, the 360 Challenge kerb weight is 1170kg (2574lbs) vs. the 360 Modena's kerb weight of 1393kg (3064lbs), a difference of 223kg (490lbs). As cars get fatter and more feature-laden, I would expect the delta for racing versions to increase a little, not decrease substantially.

Therefore, I conclude that all Ferrari "kerb weights" are excluding petrol. Anyone have evidence to the contrary?

In the US Users Manuals, however, I believe "curb weight" is quoted WITH fuel. And given the consistently higher weights of US Users Manuals vs Euro Users Manuals, this seems to provide an explanation. I guess it would be interesting to pull up the various Euro and US users manuals and see if the weight difference is consistent with the fuel capacity of each. Worked for the Stradale.

 

Also works for the Modena... the diff between curb weights in Euro and US owners manuals is exactly 154lbs, which corresponds to the 25 gallon gas tank.

How about for a modern Ferrari with different size tank?
Anyone with a Euro 550/575 manual? Euro 355 manual?
What's the quoted curb weight and quoted gallons fuel capacity?