The seller said he has new lifters, and that Precision Products will rebuild the used lifters. So I was wondering if casidiam coated lifters need the added zinc (ZDDP): http://cgi.ebay.com/ebaymotors/DEL-WEST-SOLID-LIFTER-COATED-875-chev-sb-2-ford-nascar_W0QQitemZ380111767887' Ken