Pro Star™ 555 CID Big Block Chevy Crate Engine (Longblock)

Pro Star™ 555 CID Big Block Chevy Crate Engine (Longblock)
• Dart™ Big M Block
• Full forged rotating assembly
• Dart™ Pro 1 Cylinder Heads
• 4.250 Stroke
• 4.560 Bore
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Quick Overview:
This Chevy 555 CID long block engine is brand new and assembled with high quality components.
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Custom Engraved Valve Covers

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Online Price: $8,995.00
555 CID Big Block engine featuring a new Dart™ Big M block. The Dressed Longblock build comes with timing cover, oil pan, harmonic balancer and polished Tri Star valve covers installed. These blocks are machined and assembled to exact tolerances with the highest quality parts.

This Pro Star™ 555 longblock is supplied with 2618 forged pistons, 4340 H-Beam rods and a Scat 4340 forged crankshaft.

Dart™ Big M blocks have many features that make them superior to their competition including a priority main oiling system, siamese cylinder bores with extra-thick walls and a variety of other benefits (see the Block section for more details). These new Dart™ blocks are the obvious choice for serious performance and durability.
Part Number
NEW Dart™ Big M Block
Featuring upgrades including...

True Priority Main Oiling System
Siamese cylinder bores with extra-thick walls that resist cracking and improve ring seal for more power
• Extra thick decks ensure reliable head gasket seal
• Blind head bolts don't go through to water jacket
Splayed outer bolts on middle main bearing caps
• All OE bolt holes for starter, clutch ball, etc...
Short Block Features
• Deck height 9.800"
• Rods 6.385
• Stroke 4.250
• Bore 4.560
• 2618 Forged Pistons
• Scat 4340 Forged crankshaft
• 4340 Forged H-Beam Rods
• Brass frost plugs
• Moly piston rings
• HP cam bearings
• Howards hydraulic roller camshaft
• Internally balanced
Camshaft Advertised Duration
300° Intake
308° Exhaust
Camshaft Duration @ .050"
247° Intake
255° Exhaust
Camshaft Lift
.680 Intake
.680 Exhaust
Dart™ Pro 1 Cylinder head castings

►325cc Intake Runner
►121cc combustion chamber volume
►2.25 stainless intake valves
►1.88 stainless exhaust valves
►Rectangular intake port shape
►Howards HP valve springs
►Howards chrome moly valve spring retainers

►Premium alloy:
       •Dart aluminum heads are cast from virgin 355-T61 aerospace alloy for superior strength and integrity.
►Manganese bronze valve guides extend cylinder head life and reduce stem wear.
►Hardened exhaust seats are compatible with unleaded gasoline
►Multi-angle intake seats and radiused exhaust seats dramatically increase airflow.
►Spark plug holes are machined for gasketed 3/4" reach plugs.
►Heart shaped 121cc chambers improve combustion efficiency.
►Raised spark plug location improves flame travel for a quicker, more complete burn, producing more power.
►Exhaust ports raised .300" to improve flow
Cast, machined and assembled in the USA

Additional Parts Included
• SFI rated harmonic balancer
• High capacity oil pan
• Chrome timing cover
• Pro Star polished aluminum valve covers
2 years, unlimited mileage
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Crude oil, gasoline, diesel fuel and other petroleum products can expose you to chemicals including toluene and benzene, which are known to the State of California to cause cancer and birth defects or other reproductive harm.

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