Recently did a carb conversion on my 91 5.0. I figured it would be a good time to put new lifters and pushrods in. When I finished up the motor, and fired it up- the lifters and or rockers were clattering. I thought that maybe the lifters had to prime. After about 5-10 minutes shut the car off and pulled a valve cover to investigate. My rockers arms are torqued down(25lb-ft) but rockers are loose. I'm thinking either the lifters didn't prime, pushrods are too short or lifters are a different height. They are Summit lifters and Comp Cams pushrods. What am I doing wrong??!! This was not making a peep before I swapped the lifters and pushrods.