Remember in the Pict. Irish Riches heads were sitting flat on a table. Theyll be @ 22.5* when mounted on the engine. Should be just right! BTW those are some way cool parts. Most on here are way jealous. Me included!I had a dc series in my hand today , the ports on the head over hang the carb throat so they will be to small . My other concern on these is running these with a Bolt on carb the carbs will be sitting angled like in Irish Rich's picture . So Irish Rich , have you run these heads yet ? How do they work with the Amals?