{"product_id":"eagle-chevy-pro-street-408-balanced-rotating-assembly-4140-crankshaft-w-4340-i-beam-rods","title":"Eagle Chevy Pro Street 408 Balanced Rotating Assembly 4140 Crankshaft w\/ 4340 I Beam Rods","description":"\u003cdiv\u003e\n\u003cstrong\u003eSKU:\u003c\/strong\u003e \u003cspan itemprop=\"sku\"\u003eB627144030\u003c\/span\u003e   |   \u003cstrong\u003eUPC:\u003c\/strong\u003e 793348041032\u003c\/div\u003e\n\u003cdiv\u003e\u003c\/div\u003e\n\u003ch4\u003e\u003cstrong\u003eEagle Pro Street Balanced Rotating Assembly - Chevrolet Small Block 408 ci (4.030\" Bore x 4.000\" Stroke)\u003c\/strong\u003e\u003c\/h4\u003e\n\u003cp\u003eThe Eagle Pro Street balanced rotating assembly for small block Chevrolet engines delivers a complete, internally balanced 408 cubic inch kit built around a 4140 forged steel crankshaft and 4340 forged I-beam connecting rods. Designed for street performance and moderate racing applications up to 700+ hp, this kit includes forged pistons, plasma-moly file-fit rings, and high-performance bearings – providing a reliable foundation for stroker 350 builds with improved displacement and torque.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e4140 Forged Steel Crankshaft:\u003c\/strong\u003e 4.000\" stroke with 350 main journals (2.448\") and standard SBC rod journals (2.100\").\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e4340 Forged I-Beam Rods:\u003c\/strong\u003e 6.000\" length with 7\/16\" ARP 8740 cap screws – rated for 700+ hp.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eForged Pistons:\u003c\/strong\u003e 4.030\" bore, dish or flat top (compression ratio varies by head\/chamber).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlasma-Moly File-Fit Rings:\u003c\/strong\u003e 1\/16\" - 1\/16\" - 3\/16\" ring pack for low friction and excellent sealing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClevite H-Series Bearings:\u003c\/strong\u003e Tri-metal rod and main bearings included.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInternally Balanced:\u003c\/strong\u003e No heavy metal required – ready for assembly.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRPM Capability:\u003c\/strong\u003e Safe to 6,500+ RPM with proper components.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMade in USA:\u003c\/strong\u003e Manufactured and assembled by Eagle Specialty Products.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eProduct Notes\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003ePart number: B627144030 (408 ci Pro Street kit).\u003c\/li\u003e\n\u003cli\u003eCrankshaft: 4140 forged steel, non-twist forging, nitrided for durability.\u003c\/li\u003e\n\u003cli\u003eRods: 4340 forged I-beam with ARP 8740 bolts – bushed for floating pins.\u003c\/li\u003e\n\u003cli\u003ePistons: Forged 4032 or 2618 alloy (varies by batch) – typically -18cc dish for ~10:1 compression with 64cc heads.\u003c\/li\u003e\n\u003cli\u003eBalanced to ±2 grams – ready for installation.\u003c\/li\u003e\n\u003cli\u003eTotal kit weight approximately 135-145 lbs.\u003c\/li\u003e\n\u003cli\u003eRequires 4.030\" bore block (350 block bored .030\" over).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eProfessional engine builder assembly required.\u003c\/li\u003e\n\u003cli\u003eClearance check all components (piston-to-valve, rod-to-cam, etc.).\u003c\/li\u003e\n\u003cli\u003eUse high-zinc break-in oil and follow proper ring seating procedure.\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\u003eEngine\u003c\/th\u003e\n\u003cth\u003eBlock\u003c\/th\u003e\n\u003cth\u003eBore\u003c\/th\u003e\n\u003cth\u003eNotes\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eChevrolet Small Block V8\u003c\/td\u003e\n\u003ctd\u003e350 ci (4-bolt or 2-bolt main)\u003c\/td\u003e\n\u003ctd\u003e4.030\"\u003c\/td\u003e\n\u003ctd\u003e1967-2002 SBC blocks\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStroker Builds\u003c\/td\u003e\n\u003ctd\u003eDart, World, GM, etc.\u003c\/td\u003e\n\u003ctd\u003e4.030\"\u003c\/td\u003e\n\u003ctd\u003eRequires clearancing for 4.000\" stroke\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch4\u003eWhy Choose Eagle Pro Street?\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e30+ years of crankshaft and rotating assembly expertise.\u003c\/li\u003e\n\u003cli\u003ePro Street series offers forged 4140 crank and 4340 rods at an affordable price point.\u003c\/li\u003e\n\u003cli\u003eTrusted by engine builders for street and strip 408 SBC builds.\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 What compression ratio?\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA:\u003c\/strong\u003e Typically ~10:1 with 64cc heads and -18cc dish pistons – confirm with your heads.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e Is it externally balanced?\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA:\u003c\/strong\u003e No – fully internally balanced for use with neutral balance flexplate\/flywheel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQ:\u003c\/strong\u003e Does it include a balancer or flexplate?\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eA:\u003c\/strong\u003e No – crankshaft only; uses neutral balance damper and flywheel.\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 Freight truck (heavy crate).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePackage Weight:\u003c\/strong\u003e Approximately 160–180 lbs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCrate Dimensions (approx):\u003c\/strong\u003e 42\" × 24\" × 24\".\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Eagle","offers":[{"title":"Default Title","offer_id":43467591647311,"sku":"EAGB627144030","price":2660.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1062\/7920\/files\/eagle-b627144030-408-kit-full.png?v=1763568736","url":"https:\/\/www.blackopsautoworks.com\/products\/eagle-chevy-pro-street-408-balanced-rotating-assembly-4140-crankshaft-w-4340-i-beam-rods","provider":"Black Ops Auto Works","version":"1.0","type":"link"}