Contrary to some Untrue assumption the 4A-G is a duplicate of your Cosworth BDA, (coincidental ‘A’ series designation on equally engines). You will find minor, if any, interchangeable pieces between The 2 engines, beyond it's possible some nuts and bolts. The Cosworth four-valve design began existence using the Ford Cortina https://jamesn058waz4.ourabilitywiki.com/user