The Olds 350 was basically the same size as the 455 Olds,externally,thus,it was a big block Olds.same was true of the Pontiac 326 and the Buick 350 engine (not counting the corporate 350 used by all GM divisions and based on the Chevy engine).
Speed

1954 GMC 350
1957 GMC 1/2 ton
1962 Chevy C-30
1952 Chevy 6400 dump bed project truck
'98 Harley FLSTC
'66 Pontiac Catalina
'76 Chevy 1 ton Duallie
'84 Bronco II
'78 Dodge W-200
'81 Toyota 4X4 truck