This Rigid Valve Spring Compressor on-the-car rigid valve spring compressor was designed to do away with conventional lever based or C-clamp type compressor mechanisms. The side-by-side threaded compressor's unique and inherent design allows the technician to: 1) have two free hands to work with at all times, 2) safely and easily maintain the valve spring to a fully compressed position, 3) repair valve stem seals without removing the heads, 4) cut factory alloted repair times, 5) work on all double overhead cam Saab engines ever produced (900, 9000, 9-3, 9-5, etc) from the earliest to the most recent. Patent pending.