While you're in there, you might as well check to make sure all your rocker arms are nice and tight and adjusted. You can also take a peek into how grungy the motor is. Just looking at the crud on the heads can tell you the state of the rest of the motor. Using cheap oil will show by there being a good bit in the line of sludge-type buildup on the heads. While you may be tempted to clean the crud off, personally I probably wouldn't, since it would suck to get the oil pump pickup covered in that crud. Then of course, you can have the valve covers steam-cleaned inside and out and painted/powder coated....