years ago I did this test. I pulled the heads, intake, carb, and cam from the 340 and put them all on the 360, changed the pistons so both would have almost identical compression, and no other changes to the car. The car went three tenths faster with the 360. Gears were 3.91 and the converter was a TCI break away. 340 shifted at 6k and that gave the best ET. 360 liked 5700.
