SB Ford 289 302 351W 7/16 Stud Girdle Kit w/Poly Locks Small Block Ford V-8 lightweight aluminum stud girdle kit. SB Ford 7/16 High Performance Stud Girdle Kit 289 302 331 347 351W This kit is designed provide more accurate valve lift and timing by stopping rocker stud flexing. Each set comes with aluminum stabilizers and poly locks. This kit is for standard stud spacing, and WILL NOT WORK WITH Center Bolt Valve Covers.