The 8270(200 drawbar H.P.) would be a bigger horse and would have the 18 speed powershift transmission. It weighs more also which might give you less slippage. The 8160(180 drawbar H.P.) has the 32 speed dynashift trans.(very smooth shifting) I had an 8150 before the 8160 and have been very happy with both. I guess if I had my choice, I would probably go with the 8270 just because it's the newer style. I haven't ran one in the field but my dealer says they're quite a machine. You wouldn't be disappointed with the 8160 either, it is a very good tractor. What are you running nowIJ I pull a 27 1_2 foot J.D. 980 field cultivator but it doesn't work the old girl very hard.