Ford Mustang Comp Cams - Three-Valve Thump - Tech
The JPC tool is screwed into the No. 1 cylinder, and the air compressor is attached to it. The air pressurizes the cylinder to hold the valves closed. This is important, as the compressed air allows the valvesprings to be removed without dropping the valves into the cylinder. This process will be duplicated for each cylinder. View Related Article