working o 1921 depot hack how much should I be reading when checking cylinders for psi and what is the lowside reading for a ring job
50-55 new. All cylinders should be within 10% of each other. Once you drop below 30-35, you loose about half your power. Check dry then check wet (oil). If the wet pressure goes up, it could be rings. If it doesn't, it could be valves. There are other items that contribute to low pressure. A blown head gasket and/or carbon build up.