This product is a valley cover plate intended for use on 1997-2004 GM LS1/LS6 engines and similar GM Gen III engines that have been converted from EFI to carbureted set ups. The main focus of this part is that it is absent of the knock sensor bosses contained on the stock piece which become no longer necessary when switching to a carburetor. The casting will offer a breather boss that will need to be drilled and tapped by those retaining the stock LS-6 breather configuration or for LS-1 users looking to convert to an LS-6 style. It is to be a sand cast part and will be offered in a natural aluminum finish. Note that piece will not work with LS2, LS7, LSX or any other GM GEN IV engines.