The 400 cams were low-RPM, low-duration, low-lift stuff. Relied on the cubes rather than cam.
They were also all flat tappet. If your 305 is a '87-later passenger car, it would have come with a roller lifter cam.
They were also all flat tappet. If your 305 is a '87-later passenger car, it would have come with a roller lifter cam.