OK, just found out that my motor is a 1973 350 from a car (F,A or X body)
Original specs - 145hp, 2bbl, manual trans., 4.001 bore, 3.48 stroke, 8.5:1 compression
haven't checked heads yet, but I'm pretty sure that it puts out more than 145 today.

It's got a 12bolt posi rearend, and I left two black marks about 15 feet long.