{"product_id":"sierra-18-1908-manifold-riser-spacer-for-mercruiser-gm-v6-v8-229-454-cu-in-aluminum-exhaust-riser-spacer","title":"Sierra 18-1908 Manifold Riser Spacer, 3 Inch, OEM 933220A12, Fits Mercruiser Manifold 18-1953-2","description":"\u003cp\u003eThe Sierra 18-1908 is a 3 inch manifold riser spacer engineered to fit Mercruiser exhaust manifold 18-1953-2. It is built from aluminum and is primed and painted for added durability and corrosion protection, arriving ready to install out of the box. The spacer sits between the exhaust manifold and the riser elbow, and it is designed to be used with a specific mounting kit depending on which elbow and riser combination is installed: pair it with mounting kit 18-8554 when using riser 18-1970-2, or with mounting kit 18-8555 when using riser 18-1976-2. It carries the OEM cross-reference number 933220A12, so it is a direct equivalent for that original part.\u003c\/p\u003e\u003cp\u003eThis spacer is intended for engine setups that pair with manifold 18-1953-2, including Mercruiser GM Big Block V8 454 cid engines (Models 330, 340 \u0026amp; 74L), GM Small Block V8 305-350 cid engines (Models 200, 228, 230, 260 \u0026amp; 898), and GM V6 229 \u0026amp; 262 cid engines (Models 185 \u0026amp; 205). When sealing the elbow to this spacer, elbow gasket 18-0672 is the compatible closed-style gasket for this fitment. Note that mounting the elbow to the spacer requires its own separate mounting kit rather than reusing the elbow's original hardware.\u003c\/p\u003e\u003ch3\u003eSpecifications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Sierra\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number:\u003c\/strong\u003e 18-1908\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Manifold Riser Spacer\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM Cross Reference:\u003c\/strong\u003e 933220A12\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpacer Height:\u003c\/strong\u003e 3 inches\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaterial:\u003c\/strong\u003e Aluminum\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFinish:\u003c\/strong\u003e Primed and painted\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAuto Part Position:\u003c\/strong\u003e Front\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 6.32 pounds\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Dimensions:\u003c\/strong\u003e 5.25 inches L x 5.75 inches W x 5.5 inches H\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 808282127503\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFits Manifold:\u003c\/strong\u003e 18-1953-2\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible Mounting Kits:\u003c\/strong\u003e 18-8554 (with riser 18-1970-2), or 18-8555 (with riser 18-1976-2)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatible Elbow Gasket:\u003c\/strong\u003e 18-0672\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eFitment\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eMercruiser GM Big Block V8 454 cid (Models 330, 340 \u0026amp; 74L)\u003c\/li\u003e\n\u003cli\u003eMercruiser GM Small Block V8 305-350 cid (Models 200, 228, 230, 260 \u0026amp; 898)\u003c\/li\u003e\n\u003cli\u003eMercruiser GM V6 229 \u0026amp; 262 cid (Models 185 \u0026amp; 205)\u003c\/li\u003e\n\u003cli\u003eFits manifold 18-1953-2\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eReplaces (OEM)\u003c\/h3\u003e\u003cul\u003e\u003cli\u003e933220A12\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\u003cp\u003e\u003cstrong\u003eWhat engines does the Sierra 18-1908 manifold spacer fit?\u003c\/strong\u003e The Sierra 18-1908 fits manifold 18-1953-2 and is used on Mercruiser GM Big Block V8 454 cid engines (Models 330, 340 \u0026amp; 74L), GM Small Block V8 305-350 cid engines (Models 200, 228, 230, 260 \u0026amp; 898), and GM V6 229 \u0026amp; 262 cid engines (Models 185 \u0026amp; 205).\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs 18-1908 the same as OEM part 933220A12?\u003c\/strong\u003e Yes, Sierra 18-1908 carries OEM cross-reference number 933220A12, making it a direct equivalent for that original manifold spacer.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow thick is this manifold spacer?\u003c\/strong\u003e The Sierra 18-1908 is a 3 inch spacer designed for manifold 18-1953-2.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat material is the 18-1908 spacer made from?\u003c\/strong\u003e It is made from aluminum and is primed and painted for added durability and corrosion protection.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoes the 18-1908 spacer come pre-painted or does it need to be finished after installation?\u003c\/strong\u003e The Sierra 18-1908 arrives primed and painted from the factory, so it is ready to install out of the box without additional finishing.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhich mounting kit do I need with the 18-1908 spacer?\u003c\/strong\u003e It depends on the riser installed: use mounting kit 18-8554 with riser 18-1970-2, or mounting kit 18-8555 with riser 18-1976-2, alongside the 18-1908 spacer.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat gasket do I need to seal the elbow to the 18-1908 spacer?\u003c\/strong\u003e Elbow gasket 18-0672 is the closed-style gasket that fits the 18-1908 spacer along with manifold 18-1953-2.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow much does the 18-1908 manifold spacer weigh?\u003c\/strong\u003e The Sierra 18-1908 weighs 6.32 pounds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat are the package dimensions of the 18-1908 spacer?\u003c\/strong\u003e It ships in a package measuring 5.25 inches long by 5.75 inches wide by 5.5 inches high.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eCan I mount the elbow directly to the 18-1908 spacer using the elbow's original hardware?\u003c\/strong\u003e No, mounting an elbow to the 18-1908 spacer requires its own separate mounting kit rather than reusing the elbow's original mounting hardware.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWhat is the difference between the 18-1908 and the 18-1985 spacer?\u003c\/strong\u003e The 18-1908 is a 3 inch spacer for manifold 18-1953-2, while 18-1985 is a 6 inch spacer for the same manifold and requires its own separate mounting kit (18-8556).\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eIs the Sierra 18-1908 a genuine Sierra part or a generic aftermarket copy?\u003c\/strong\u003e The 18-1908 is a genuine Sierra International manifold riser spacer, manufactured as a direct equivalent to OEM part 933220A12.\u003c\/p\u003e","brand":"Sierra","offers":[{"title":"Default Title","offer_id":48988089221339,"sku":"SIE-18-1908","price":141.1,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0839\/7586\/4539\/files\/Untitled-1__89250.1753840675.500.750.jpg?v=1785188146","url":"https:\/\/www.goodvibesmarina.com\/products\/sierra-18-1908-manifold-riser-spacer-for-mercruiser-gm-v6-v8-229-454-cu-in-aluminum-exhaust-riser-spacer","provider":"Good Vibes Marina","version":"1.0","type":"link"}