It seems to me the older trucks like my '94 are the low rev'ers. PLUS, the springs in the govenor get weaker as they age and the r's go down. My truck would only rev to 2,200 before the injector pump was rebuilt. After the rebuild, the r's increased to 2,500 because the stock govenor springs were shimmed/replaced. The Piers springs, especially the smallest inner spring is much stiffer than the factory spring, so BAM, big RPM's for the first time in my '94! I can't tell you how much easier and more enjoyable the truck is to drive now.