hey bull8705!
The 289 in your '61 is a STUDEBAKER V8 introduced around 1951 or 52. It was relatively advanced and quite light weight for its day; Dean Moon (of Moon Equipped, Mooneyes, etc,) swapped one into his '34 Ford coupe in the mid-50's, and that man knew engines and their potential!
The PACKARD V8 was a heavy, big-displacement engine (about 370 cubic inches) that was swapped into a few Hawks after '56. They were VERY fast in a straight line and did well at the drag strips.