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- Big Block Chevy Marine Base Engine
- 496ci / 460HP / 515TQ
- 2-Piece Rear Main Seal
- These engines require neutral balance balancers and flywheels
Engine Break-In Procedure
Use or break-in oil or conventional (non-synthetic) multi-viscosity oil with zinc additive for the first 30 hours of operation. Avoid hard acceleration for sustained periods. Periodically change the engine speed to help seat the rings. While the engine is running, be sure to check oil pressure and coolant temperature, and check for fluid leaks, such as oil, fuel, and coolant/antifreeze. Also listen for any unusual sounds. Should you hear an unusual sound, shut the engine off, check for the source, and correct it.
Engines with flat tappet cams only - Start the engine and bring it to 2,000 RPM. Get the engine running smoothly. Then vary the engine speed from 1,800-2,200 RPM in a slow acceleration/deceleration cycle for 30 minutes. This is necessary to provide adequate oil splash and lifter rotation to properly mate each lifter to its lobe.
After 30 hours of operation change the engine oil and filter. For flat tappet cam engines, continued use of oil with zinc or a zinc additive for the life of your engine is recommended.
- Marine 496ci Stroker Engine
- Bored .060" over
- 2-Piece Rear Main Seal
- 4 Bolt main
- Brass Freeze Plugs
Rotating Assembly: - Cast Steel Crank
- 4340 Forged Rods w/150,000 psi rod bolts
- Forged Flat Top Pistons
- Hastings moly rings
- Compression: 9:1
- Internally Balanced
- Melling High Volume Oil Pump
- Heavy duty double roller (high performance) timing set
Cylinder Heads: - GM Cast Iron Oval Port w/screw-in studs and guide plates
- 2.25" Intake/1.88" Exhaust Valves
- 1.509 dia. Valve springs w/ damper
- Hardened retainers & keepers
- Hardened Pushrods
- Long slot rockers with positive lock adjusting nuts
Camshaft Specs: - Hydraulic Flat Tappet
- Duration @ .050'' Lift: 226 Intake / 236 Exhaust
- Lift: .544'' Intake / .547'' Exhaust
- Lobe Separation: 112 Degree
Included Accessories: - Marine Intake Manifold
- Cad Plated Marine Oil pan
- Non-Weighted 8" Diameter Balancer
- Chrome Valve Covers
- Chrome Timing Cover
Dress Model Adds: - Marine 800 CFM Carburetor
- Marine Mechanical Fuel Pump
- Ignition System w/ plug wires and coil
Note: Your BluePrint engine was dyno tested with the parts and specifications listed below. If you prefer to install a different part, your engine may not produce the horsepower recorded on your dyno sheet.
- Part Number: MBP4960CT
- Fuel Delivery Type: Carbureted
- Spark Plug: NGK 2817 w/ .045" Gap
- Spark Plug Gap: .045"
- Harmonic Balancer: Non-Weighted 8" Diameter
- Flexplate/Flywheel: Non-Weighted
- Stall Converter: N/A
- Intake Manifold: Marine Single plane
- Fuel Recommendation: 91 Octane
- Timing (Initial/Total Advance): Initial timing - 10-16° and Total timing 32-34°
- Firing Order: 1-8-4-3-6-5-7-2
Blueprint Marine Engines are a great choice for reliable high performance pleasure craft engines. The block is bored .060'' over, then honed on a computer controlled machine to within .002'' straightness and roundness, the cylinders are also sonic tested for thickness to ensure a solid foundation. The block also feautures a square and parallel decked surface and an align honed main bearing bore. All rotating assemblies are balanced within 2 grams on a computerized balancer. Blueprint Marine Engines are dyno tested and include dyno sheets.
Best of all they feature a 1 year/unlimited hours warranty (pleasure craft only).
Recommended Fuel: 91 Octane
Block:Items You Need
