DB, the early Sunbeams held the land speed record for sometime with a blown (supercharged) version of this engine ,it's a 3 litre to 3.5 litre twin cam with no head, all mounted from the sump!, a 13 gear chain, bronze and steel, driven from the crankshaft running the cams, it was this engine that influenced the Jaguar straight 6 of 60s and 70s, these guys built a custom Sunbeam from old parts with a shortened chassis and a new fully blown 3.5 litre motor that took the record for the Shelsley Walsh hill climb in the UK about 12 years ago ,a yearly event since 1910!
BTW the Alpines and the Tigers (which had I think had a Chevy V8 in them) were made by Sunbeam Talbot and not connected to the old Sunbeams pictured here.
Giles