BPQ #063 solved: BMC XC9000 prototype 1956 leading evtl to Austin 1800

[BattlePorQ]

Doesn't it look somewhat familiar?

[Autowelo65]

Maybe it's an early prototype of BMC ADO16 car, it was called XC9002 as far I know

[Carnut]

BattlePorQ hasn't logged on here since January 2023 so I don't think you'll get an answer from him any time soon...

So I'll answer you: it's not an XC9002 prototype, but you've got the right manufacturer so it's not a million miles away from the right answer...

[Autowelo65]

Maybe it's a XC9000 then?

[Carnut]

Yes, it is the first XC9000 prototype.
Would you like to explain when it was built and exactly why at the time? It did of course evolve into something else by the time it finally appeared as a finished car quite a few years later, but since you're the one answering the question rather than me I'd like you to describe its purpose when it was built.
Needless to say the puzzle is locked for you.

[Autowelo65]

Well, actually, I don't know so much, but I'll try.
I found this. It was developed by team under leadership of Alec Issigonis in 1956-57 and that it was a 1.5 liter RWD saloon car, later it was renamed to XC9001, it was a FWD version of XC9000 and 9001 got restyled by Pininfarina. In 1960, it was renamed XC9005 and got 1.8 liter engine. XC9005 evolved into a ADO17 family of cars (also known as "Landcrab") and was launched in production in 1964 as Austin, Morris and Wolseley.

[Carnut]

Yes, that's all correct.
They didn't seem to have any particular car in mind for it when it was first built in 1956, just that Issigonis thought it would be a good idea to use his Mini ideas for a bigger RWD car!
But then it was eventually used as the development prototype for the Austin 1800 introduced in 1964, as you say; see here: 

https://www.autopuzzles.com/forum/2011-39/solved-mjw-423-bmc-issigonis-project-xc9001-1958/msg160996/#msg160996

So here's your first point and it's moved to Solved. Well done.