Combines 1666 what will it doIJ

We have a 1666 and it has good power and capacity. In that heavy of a crop I would go with a 25 foot head. You could go about 3 to 4 mph in good dry conditions. You would lose power in wet conditions much faster than a 1688. If you want to use a 30 foot head I would go with a 1688 and an AFX rotor. They aren't going to make an AFX for the 66.

We have a 1989 1660 with a 25' 1010. This past summer we werre going 4+ mph in 40 bpa wheat.