Big lift cams and wide durations with little to no valve reliefs , it is just about a must. Here's my take. If you have a QUALITY name brand chain like cloyes true roller, and a known cam maker like com,or lunati it pretty much stays within 1 degree. But MP cams and chains are just about always off. Piston to valve is critical too. You will feel better if you degree it, and it doesnt take but a few minutes when you have all the stuff