I had a 5 ft. double disc on my bx 2660 with a loader. it has 25.5 hp and it took it all to pull it and i had to have the loader on to turn or it would slide. Our soil is fairly heavy in our area. Hope this helps Barry
I found it on Northern Tool's website. They recommend 35hp & up. The shipping weight is 790 lbs. and I'm pretty sure the 3ph will handle that. I'll keep my eye out for a 4 1/2' one. They recommend 20hp & up for that one. I'll be running it in sand and light loam and I think that the tractor weighs enough and has a stout enough drive train that I can shift down and make up for the 5 hp deficit