Main Stud Kit, 4-Bolt Main Hex Nut AR154-5607 Aero Clamps NPT Male-Female Extension 3/8" 372-06S

NPT Male-Female Extension 3/8" 372-06S AF372-06S Black Finish

4L 03/03-05

AF503-16BLK

AF704-08BLK

Exhaust valve diameter stays the same with a little more flow from its larger runner volume

Main Stud Kit, 4-Bolt Main Hex Nut AR154-5607 Aero Clamps NPT Male-Female Extension 3/8" 372-06SMain Stud Kit, 4 Bolt Main Hex Nutfits SB Ford 351 Windsor Dart Iron Eagle Block AR154 5607 154 5607 There are many important reasons to use ARP main stud kits, including the elimination of main cap walk and fretting, as well as protecting the threads in your engine block. All kits come complete with hardened parallel ground washers and high quality nuts. Some applications have provisions for mounting windage trays and have specially designed standoff