Not necessarily. Among other factors, the type of wood will determine capacity.
I purchased a Woodmax 8M for my LS XJ2025h that has less than that on the pto (17hp, I think) When it arrived, I thought I had made a major mistake and ordered an 86H, but since the 86 was back ordered, I decided to try the 8M with the XJ2025h.
Bottom line, it was excellent for cedar (Juniper) sometimes over 6" in diameter. The XJ2025h would bog down slightly when something that large hit the blades, but the LS would increase the throttle and the 8M would chip it at the same rate that it would chip a three inch piece.
The 8M has a huge and heavy (200+ lb) flywheel that is driven by a belt drive that increases the flywheel rotation to 1120 rpm. I used it for around 120 hours and cleared most of the low cedar on our lot. My wife _loved_ the 8M after years of not being able to use a 6hp patriot because of it's difficulty and danger.
The 8M has a mechanical feed, and for anyone considering it, I strongly recommend the hydraulic feed model despite the increased cost. The mechanical feed did jam on several occasions and there are problems when it does. The emergency feed disconnect is under so much pressure when a jam does happen that the bail lever that decouples the gearbox bends without disconnecting, so, the immediate result is that the feed drive belt burns up. (I learned that in the event of a jam to go straight for the PTO switch on the tractor.)
The
8H, doesn't have that problem.
In addition, I learned from using the 86H after I sold the 8M that the feed reversal alone is worth the extra cost. It absolutely ends feed jams.
An extra benefit is that since the hydraulic feed speed is adjustable, that further increases the ability to chip large diameters and harder wood by reducing the feed speed.
Final notes would be that the 86H doesn't have the same capacity, but it is smaller and lighter, so it's more manageable by this aging body after we finished most of our clearing. In addition, the 86 hopper folds so it requires about half the storage space as the 8M did.
I'm obviously a
WoodMaxx fan. I'll be glad to answer any additional questions that anyone might have, including a number of minor mods that I made to make using the 8M more pleasant.
Beverly Howard