Sierra Universal Center Riser Manifold. Sierra Manifolds are painted, packaged, and leak tested. Port and Starboard. For GM Small Block (V8) 305-350 cu. in. Replaces Barr CHV-1-83. Use Sierra 18-0604 Exhaust Manifold Gasket Set.• Sierra Part #18-1997-1.FITSChriscraft: 283, 302, 307, and 350 CID enginesCrusader: 283 and 327 CID engines thru 1964; 305, 307, and 350 CID engines 1965 and laterDaytona: 200-283 and 300-327Flagship: 283, 327, and 350 CID enginesPacer: 305, 307, and 350 CID engines 1965 and laterMercury: 190, 198, 225, 250, 270, 228, 898, 260, 255, and 280 modelsOMC: 283, 305, 307, and 350 CID engines 1968-1980Volvo: 307 and 350 CID engines GM Small Block (V8) 305-350 cu. in. Port & starboard Painted & leak tested | Sierra Universal Center Riser Manifold, Part #18-1997-1