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Looking for aftermarket parts to modify or upgrade your 1978 GMC C15 with valve cover gaskets? At Tunersports.com we carry a huge selection of the top name brand performance valve cover gasket parts and accessories.
 SHIPS FROM MANUFACTURER C15268-125Race inspired designs and materials ensure that these valve cover gaskets will perform well above the OE standard. Cometic valve cover gaskets surpass the quality and ability of typical cork or paper gaskets offered by other manufactures. Withstands blowing out, over tightening, and high vacuum all ... Cometic Mark-IV BB V8 .125in Fiber Valve Cover Gskt Set-Fits Brodix BP DN-9-9 Deg Valve Angle Heads 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $109.63 |
 SHIPS FROM MANUFACTURER C15302Cometic Valve Cover Gaskets are engineered to meet or exceed OEM quality and fitment. In many cases improvements to the OEM design have been made to offer a superior product. Made from a strong .094" Kevlar Fiber material that wont allow over-tightening and withstand high vacuum environments.... Cometic Chevrolet Gen IV/V/VI .188in Fiber Valve Cover Set 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $76.42 |
 SHIPS FROM MANUFACTURER C15460A premium high temperature, high-density, creep-resistant material that requires no re-torquing and is fuel resistant. All Cometic fiber materials are asbestos free and require no additional sealants.... Cometic Chevy Mark-IV GM Gen-V/VI BB V8 .094in Fiber Valve Cover Gskt-Fits Brodix SR20 Series Heads 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $52.47 |
 SHIPS FROM MANUFACTURER C5343-094Race inspired designs and materials ensure that these valve cover gaskets will perform well above the OE standard. Cometic valve cover gaskets surpass the quality and ability of typical cork or paper gaskets offered by other manufactures. Withstands blowing out, over tightening, and high vacuum all ... Cometic Chevrolet Mark-IV Big Block V8 .094in Fiber Valve Cover Gasket - Fits Brodix Big Brodie Head 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $62.01 |
 SHIPS FROM MANUFACTURER C5343-1880.188" ML Valve Cover Gasket. Brodix Big Brodie Head. Cometic Aramid Fiber is a premium hi-temperature, hi-density, creep resistant material that requires no re-torqueing and is fuel resistant. All Cometic fiber materials are asbestos free and require no additional sealants.... Cometic Chevrolet Mark-IV Big Block V8 .188in Fiber Valve Cover Gasket - Fits Brodix Big Brodie Head 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $62.01 |
 SHIPS FROM MANUFACTURER C5973Race inspired designs and materials ensure that these valve cover gaskets will perform well above the OE standard. Cometic valve cover gaskets surpass the quality and ability of typical cork or paper gaskets offered by other manufactures. Withstands blowing out, over tightening, and high vacuum all ... Cometic GM Small Block 18/23 Degree V8 NBR Steel Spline Valve Cover Gasket 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $52.47 |
 SHIPS FROM MANUFACTURER C5973-2Race inspired designs and materials ensure that these valve cover gaskets will perform well above the OE standard. Cometic valve cover gaskets surpass the quality and ability of typical cork or paper gaskets offered by other manufactures. Withstands blowing out, over tightening, and high vacuum all ... Cometic Chevy Gen-1 Small Block V8 .188in Molded Rubber Valve Cover Gasket Set - 18/23 Degree Heads 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $70.97 |
 SHIPS FROM MANUFACTURER C5975Race inspired designs and materials ensure that these valve cover gaskets will perform well above the OE standard. Cometic valve cover gaskets surpass the quality and ability of typical cork or paper gaskets offered by other manufactures. Withstands blowing out, over tightening, and high vacuum all ... Cometic Chevrolet Mark-IV Big Block V8 .188in Rubber Valve Cover Gasket 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $52.47 |
 SHIPS FROM MANUFACTURER C5975-2Race inspired designs and materials ensure that these valve cover gaskets will perform well above the OE standard. Cometic valve cover gaskets surpass the quality and ability of typical cork or paper gaskets offered by other manufactures. Withstands blowing out, over tightening, and high vacuum all ... Cometic Chevrolet Mark-IV - GM Gen-V/VI Big Block V8 .188in Molded Rubber Valve Cover Gasket Set 1975-1978 GMC C15 Base / High Sierra / Sierra Classic / Sierra Grande 1977-1978 GMC C15 Heavy Half 1978-1978 GMC C15 Street Coupe $70.97 |