Horsepower ratings, in the early 70's changed to NET HP. It was at a lower RPM, I believe 3500 and included accessory loads. At the same time, our marine engines (Chrysler) remained nearly the same as mid to late 60's. The 318 till 95 was
235@4600, the 440 was 300-330-335-350 (335 had 2 4bbls, 350 was a 6 pack) @4000, till 80 after that the 440 was 330 till mid 80's, all with Carter AFB's and 8.2-8.5 compression. The loss of compression was only a 5-7% loss of HP, I bought my last new 440's in 86. If I was so inclined to want a possible 200 mph Imperial, I would use my 81. Since they were used in NASCAR racing, and the most aerodynamic Chryslers at the time, it would also be tubocharged, with a manual trans. The calculations that have been noted for theoretical top speeds, have not addressed torque converter loss, tire slippage, or aerodynamic loss. These could easily exceed 25%. Ya'll have a nice day, Dave.
