The way to answer this kind of question is to look up the lens' flange-focal-distance, also called flange-to-film distance (a) and the camera's minimum flange-to-film distance (b). If a >= b the lens will make infinity on the camera.
Short answer, 75/5.6 and 75/8 Super Angulons will focus to infinity on a 4x5 Pacemaker Speed Graphic.
Thanks. It was a rhetorical question, though, so the OP would consider that a Speed Graphic does have some limitations as far as lenses go. Based on your information, the 75mm SA f/5.6 and f/8 should work fine.
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