So far no kit I've used from Source has been ready to run. Admittedly I haven't used one in a couple years. But the cranks are usually within factory tolerances for taper and clearances. But they have taper and the clearances will vary journal to journal. The rods - they will need the big ends re-sized once the bolts are cycled with the right lubricant (the factory does not use the ARP lube so they are not torqued properly when finish machined). The pin ends will need honed and against the advice of the manifacturer - sand paper is not the way to do it. In terms of balancing - the rods in total are weight matched. However, when it's balanced the ends are weighed seperately - and every set has needed the rods worked to get them truly weight matched. The best part of the kits are the pistons. Which are pretty good over all.