ARP 1343609 Sb Chevy Ls1 Rod Bolt MPORTANT NOTE: MUST HAVE 2 different length primary head bolts plus a third smaller bolt. There is a Mid-Year split on the head bolts, If you have ALL SAME Size head bolts this kit is NOT for YOU, see part 134-3610. DO NOT BUY THIS KIT until you have pulled the head and verified the size.