Crankshaft - 3.875 in Stroke - Internal Balance - Forged Steel - 2-Piece Seal - Small Block Chevy - Each

Eagle Chevy 400 Small Block Forged Internally Balanced Crankshaft

Eagle forged 4340 steel Cranks feature a non-twist forging, .125" fillet radiuses for superior strength so chamfered / narrowed bearings required, nitrided surface and micropolished. Intended for the most demanding applications.

Additional Information

Forged 4340 Steel Crank - Chevrolet 400, 3.875" Stroke, INTERNAL BALANCE.

Application Summary

CHEVY 400

Part Type

Engine Crankshaft

Product Overview

Eagle Crankshafts feature exceptional strength and quality at a reasonable price. Eagle cranks are forged in a non-twist forging and undergo a multi-stage heat treatment process as well as stress relieving, shot peening, and nitriding. They are magnafluxed and sonic tested to insure quality. Every journal is micropolished to a 3 or better R.A. On all journals, a 0.125" radius is used to increase strength, so chamfered bearings must be used. The perfect choice for engines up to 1500HP!

*4340 Steel Crankshafts*
Eagle forged 4340 steel crankshafts are forged from SAE 4340 steel, feature a non-twist forging, multi-stage heat treat process, stress relieving, shot-peening, and nitriding for superior strength and reliability in the most demanding applications. Each journal is micropolished to a 3 r.a. or better. A .125" radius is used to increase strength, so chamfered bearings must be used. All use a Ford rod journal width regardless of journal diameter. All are designed for internal balance. These are the perfect choice for applications up to 1500 hp.

Eagle Forged 4340 Steel Crankshafts are also available in 'Lightweight' versions - Counterweights are knife-edged for reduced weight and less windage. Typical weight reduction is 5-6 lbs.

*Cast Steel Crankshafts*
Eagle cast steel crankshafts offer an excellent alternative to a factory cast crank. All radii are .092" so O.E. style bearings can be used. Target bobweight is +/- 2% GUARANTEED! Recommended for use up to 500hp. Designed for 28 in-oz. external balance.

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Product Details

Reference Information

Crankshaft, 2-Piece Seal, Internal Balance, Forged 4340 Steel, 3.875 in. Stroke, Chevy, 400, Each

Eagle forged 4340 steel crankshafts are great for high performance applications. They feature non-twist forging, undergo a multi-stage heat-treatment process, and are stress-relieved and shot-peened. These cranks are X-rayed, magnafluxed, and sonic-tested, so you know you're getting a top-quality piece. Each crankshaft has chamfered oil holes for improved oiling, a .125 in. radius on rod and main journals for increased strength, and the journals are precision-ground and micro-polished to less than 5 R.A. A target bob weight of +/- 2 percent greatly reduces balancing time. Many options are available; order the model recommended for your year/make and engine application.