Often it's also for regulatory reasons, particularly around emissions. Larger engines require more complex emission controls, so often an engine (including e.g.

Often it's also for regulatory reasons, particularly around emissions. Larger engines require more complex emission controls, so often an engine (including e.g. a JD) will be sold with a nameplate of say 74hp and chip-limited. It could very likely get its maximum efficiency at that output. We have a vendor that sells equipment with a built-in engine, and we use some of the power from that engine to run other equipment. Under Tier-4 emissions requirements the vendor moved to all-digital controls, which have a much tighter control on power output. Our customers are annoyed that they can't get the same amount of power out of the new equipment. Our vendor tells us, unofficially, you could tweak the ECU and get more power out, but we're not going to do that to equipment we're selling, and we're not going to tell our customers to do that, because it would violate the legal restrictions on The operation of that equipment.