{"product_id":"acl-chevrolet-v8-267-305-327-350-1967-98-engine-crankshaft-main-bearing-set","title":"ACL Chevrolet V8 267-305-327-350 1967-98 Engine Crankshaft Main Bearing Set","description":"\u003cdiv\u003e\n\u003cstrong\u003eSKU:\u003c\/strong\u003e \u003cspan itemprop=\"sku\"\u003e5M909A-STD\u003c\/span\u003e \u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003ch4\u003e\u003cstrong\u003eACL Race Series Standard Size Crankshaft Main Bearing Set - Chevrolet Small Block V8 267 \/ 305 \/ 327 \/ 350 (1967-1998)\u003c\/strong\u003e\u003c\/h4\u003e\n\u003cp\u003eThe ACL Race Series standard size main bearings for pre-1986 Chevrolet small block V8 engines (267, 305, 327, 350) provide high-strength tri-metal construction designed for performance and race applications. Featuring a hardened steel backing, leaded bronze intermediate layer, and precision electroplated lead-indium overlay, these bearings deliver increased load capacity, better embeddability, and superior oil clearance consistency – ideal for rebuilt or high-performance SBC engines using factory or standard crankshaft main journals.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTri-Metal Construction:\u003c\/strong\u003e Hardened steel back + copper-lead intermediate + lead-indium overlay for maximum fatigue resistance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRace Series Design:\u003c\/strong\u003e Increased eccentricity and crush for better oil clearance and load distribution.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStandard Size:\u003c\/strong\u003e STD dimensions direct replacement for factory bearings (2.448\" \/ 2.449\" main journal).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision Tolerances:\u003c\/strong\u003e Manufactured to ±0.0001\" tolerances for consistent oil clearance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh Load Capacity:\u003c\/strong\u003e Supports moderate to high horsepower SBC builds (up to 700+ hp with proper prep).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOil Groove Design:\u003c\/strong\u003e 3\/4 groove in upper shells for improved oil supply.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMade in Australia:\u003c\/strong\u003e Produced by ACL to ISO 9001 quality standards.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eProduct Notes\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003ePart number: 5M909A-STD (set of 5 main bearings, full engine set).\u003c\/li\u003e\n\u003cli\u003eFits pre-1986 small block Chevrolet V8 engines with 2-piece rear main seal and standard main journal size.\u003c\/li\u003e\n\u003cli\u003eCompatible with 267, 305, 327, 350 ci engines (1967-1998) does NOT fit 400 SBC or one-piece seal blocks.\u003c\/li\u003e\n\u003cli\u003eAvailable in undersizes (.001\", .010\", .020\") contact for other sizes.\u003c\/li\u003e\n\u003cli\u003eRecommended for performance and race engines not for stock replacement.\u003c\/li\u003e\n\u003cli\u003eIndividual bearing weight approximately 60-70 grams (full set ~1 kg).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eDirect replacement requires engine disassembly (crankshaft removal).\u003c\/li\u003e\n\u003cli\u003eProfessional engine builder installation recommended.\u003c\/li\u003e\n\u003cli\u003eVerify crankshaft journal condition and plastigage clearances during install.\u003c\/li\u003e\n\u003cli\u003eUse high-zinc engine oil or break-in additive for proper bedding.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eThis Part Fits\u003c\/h4\u003e\n\u003ctable border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eYear\u003c\/th\u003e\n\u003cth\u003eMake\u003c\/th\u003e\n\u003cth\u003eModel\u003c\/th\u003e\n\u003cth\u003eEngine\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e1967-1998\u003c\/td\u003e\n\u003ctd\u003eChevrolet\u003c\/td\u003e\n\u003ctd\u003eCamaro, Corvette, Chevelle, Nova, Truck, etc.\u003c\/td\u003e\n\u003ctd\u003e267 \/ 305 \/ 327 \/ 350 SBC V8 (2-piece rear seal)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e1967-1998\u003c\/td\u003e\n\u003ctd\u003eGMC\u003c\/td\u003e\n\u003ctd\u003eSierra, C\/K, Suburban, etc.\u003c\/td\u003e\n\u003ctd\u003e305 \/ 350 SBC V8 (2-piece rear seal)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUniversal\u003c\/td\u003e\n\u003ctd\u003eAny\u003c\/td\u003e\n\u003ctd\u003eSmall Block Chevrolet V8\u003c\/td\u003e\n\u003ctd\u003e267-350 ci pre-1986 with standard main journals\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch4\u003eWhy Choose ACL Race Series?\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eAustralian manufacturer with decades of motorsport heritage trusted by engine builders worldwide.\u003c\/li\u003e\n\u003cli\u003eRace Series bearings proven in high-horsepower street and race SBC engines.\u003c\/li\u003e\n\u003cli\u003eSuperior materials and tolerances vs. OE and many aftermarket brands.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e Are these for main or rod bearings?\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA:\u003c\/strong\u003e Crankshaft main bearings 5 pieces for full V8 set.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e Do they fit 400 SBC or one-piece seal blocks?\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA:\u003c\/strong\u003e No, 400 SBC and post-1986 one-piece seal blocks use different main bearings (5M909P series).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e What oil clearance?\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA:\u003c\/strong\u003e Typically 0.0015\"-0.0025\" with standard crank plastigage recommended.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eShipping \u0026amp; Handling\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eMethod:\u003c\/strong\u003e Standard ground shipping.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Weight:\u003c\/strong\u003e Approximately 2–3 lbs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBox Dimensions (approx):\u003c\/strong\u003e 8\" × 6\" × 2\".\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"ACL","offers":[{"title":"Default Title","offer_id":43815515455567,"sku":"ACL5M909A-STD","price":39.78,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1062\/7920\/files\/acl-5m909a-std-main-set.jpg?v=1763568627","url":"https:\/\/www.blackopsautoworks.com\/products\/acl-chevrolet-v8-267-305-327-350-1967-98-engine-crankshaft-main-bearing-set","provider":"Black Ops Auto Works","version":"1.0","type":"link"}