What would be an average compression test reading for a 318?

An average compression test reading for a Chrysler 318 engine typically ranges from 150 to 190 psi across all cylinders. Variations can occur due to factors such as engine wear, mileage, and maintenance history. It's important to have relatively uniform readings among the cylinders; significant discrepancies may indicate potential issues like worn piston rings or valve problems. Always consult a service manual for specific specifications related to your engine's year and model.