H2O T-20970 3" Exhaust Manifold Riser Elbow Mercruiser 98504A3 Sierra 18-1970-1 GLM 51110

DetailsReplaces: Mercruiser Part# 98503 and 98504, Barr Part# MC-20-98504 and Sierra Part# 18-1970-1Fits: Models 185, 200, 205, 228, 230, 260,330, 340, 898, and 7.4L Used in: GM V6 229 & 262 cu.in., GM Small Block V8 305-350cu.in., GM Big Block V8 454 cu.in.Mounting Hardware & Gasket not included About H20 Performance Parts H2O has been a private label manufacturer of aftermarket exhaust manifolds, risers, elbows and spacers for the marine industry since 2010. In 2013 we launched our own brand, H20 Performance Parts, as an additional avenue to provide high-quality marine exhaust components at a cost-effective price. By combining the latest tooling and an innovative casting procedure, H2O manifolds are produced with uniform wall and water jacket thicknesses; resulting in exacting fit and performance while eliminating traditional leak points. The material used for each casting is a high-grade cast iron that is continually tested to ensure a consistent mix and melt and to provide structural integrity and strength. Every mounting surface on every manifold, riser and spacer is CNC machined to guarantee an excellent gasket mating surface. Every component is 100% leak tested and coated with a baked enamel surface before leaving our manufacturing facility to provide an high quality product that looks as good as it performs. H2O Performance Part’s Warranty All of our marine exhaust manifolds, risers, and exhaust connectors are warrantied against defects in workmanship and/or material to the original purchaser for a period of three years from the date of purchase, excluding commercial marine usage.

• Replaces Mercruiser 98504A3 Sierra Marine 18-1970-1 GLM 51110 Osco 8503A Barr MC-20-98504
• High quality, uniform wall thickness, clean exhaust passages
• Shot peened for smooth external finish
• All mounting surfaces CNC machined to guarantee exacting gasket mating surface
• Leak tested and coated with a baked enamel from the factory