Not an expert but this is how I understand the horse power issue. The engine gross hp would be the horse power the engine is capable of producing. However, everything operated by that engine reduces the amount of hp available to do the work you want done. The biggest hp killer seems to be the hydrostatic transmission. For example, an L2800 has 30 hp (gross) yet at the pto it is rated at 25 hp for a manual shift and 23.5 hp for hydrostatic transmission. Usually, equipment manufacturers will list a suggested hp rating for the piece of equipment they sell. If I were buying implements for my tractor I would buy according to the gross hp rating. Say my pto hp is rated at 26 hp but my tractor is rated at 32 hp gross, then I would buy implements rated for tractors having 30-35 hp. As far as ground engaging implements I think having the 4 wheel drive is like having another 10 hp. My old tractor was 40 hp and 2 wheel drive. When I would sink the spring tooth harrow down as far as it would go the tractor would spin the wheels. My new tractor is 34 hp and 4 wheel drive and it pulls the harrow in 4 wd like nothing is back there. I also try to buy implements that are only wide enough to cover the tracks left by the rear wheels. With my tractor that is a width of 5 feet. However, I wouldn't hesitate to pull a 6 foot mower if that is what I had. There are others on this forum who know a lot more than I. They can explain better and clear up any inaccuracies in my understanding. Hope this helps.
