If nothing else, the thinking behind the 99kW/135hp Valtra-Valmet 8350 HiTech should stir debate. The theory is that by reducing engine rated speed to 1,800rpm from the more conventional 2,000rpm plus, the tractor should be quieter and more economical, too. There is no denying the logic, but what of the other less obvious effects of reducing engine revs on tractor performance? Our test seeks to provide the answers