Longest engine evolutions

[928]

I thought the A series was OHV to define it from the side valve lumps that preceded it

[Bryan]

I thought the A series was OHV to define it from the side valve lumps that preceded it

If these blogs are correct, the B-series was a scaled-up development of the 1200cc OHV developed for the post-war A40 (from the 1932 side-valve Austin 10 engine), and the A-series was a scaled-down version of it.

Austin 10 side-valve
A-series history
B-series history