I've run a 2366 with an 8-30 corn head in 160-200+ bu corn and it handles it fine, could run 3-6 mph. But it is also a lot more of a machine than a 1460, more horsepower and probably more refined as an overall combine since it is newer. I did encounter one time when I overloaded the sieves from too much grain. The corn was 210+ and the head and rotor were taking it, but just too much for the seives. That was the round we were using for a yield test and I had the rep. riding in the combine with me. He probably enjoyed that. I think you would be able to handle an 8 row head with your 1460, and will probably be at your 2.5-3.5 mph, if not any faster. Have you thought about a 1480IJ It would be almost the same as the 1680, just an earlier series and still within your budget.