Quote Originally Posted by pallmall View Post
Originally built for the Owen Organisation to race while their new 4 cylinder 2.5 BRM was being built this is another car that had a chassis swap. The BRM team borrowed the Bira car and crashed it slightly, rebuilding the Bira car with their chassis before returning it to Bira
Not quite, PM

Bira's 250F was crashed by a BRM driver, so the Owen Organisation gave Bira theirs, complete with his chassis number, then repaired his, with their own chassis number

To put it another way, the Amon/Southward car started as Bira's (2504) and was then taken over by the Owen Organisation (as 2509)

The car Bira won the 1955 NZ GP with, and which Ross Jensen later raced with the Piccolo body, had started out as the Owen car (2509) before being swapped and renumbered 2504 during 1954

No-one ever said sorting out 250Fs was easy!