Shelby 427 FE Aluminum Block

Fully redesigned, the Shelby 427 Alloy FE block is 45% lighter yet stronger than the factory cast iron version. It retains the original factory engine mounting bosses and bell housing bolt pattern, making it a bolt-in replacement for 390/427/428 cast iron FE blocks. The Shelby FE block is fully CNC-machined and comes ready for engine assembly.

The Shelby block offers these premium performance features:

• • Deep lifter valley reinforcing webs, combined with thick oil pan rails and main webs, maximize block strength.
  • A thick 0.750-inch deck provides the foundation needed for maximum head gasket sealing and retention.
  • A priority main oiling system ensures oil flow reaches the main bearings first, before the cam bearings, by raising the oil gallery adjacent to the camshaft bore. This maximizes crankshaft longevity.
  • Strong enough to support over 1,500 horsepower.
  • Shelby’s FE alloy block delivers superior bottom-end stability at high RPM.

This is accomplished by:

• An extended skirt design.
• 2, 3, and 4 main caps are cross-bolted with four cross bolts each. The main caps are billet steel, and cap alignment is further enhanced by an integral dowel section in the main studs.
• Steel caps allow moderate bearing clearances for cold starts.

Centrifugally cast ductile iron cylinder sleeves are fitted into the block with an interference step fit, ensuring precise, non-shifting sleeve positioning. Cylinder walls are siamesed, and revised cooling passages eliminate cooling issues on the street or track.

The block requires special Shelby head studs, available separately. Unlike a stock block, where the head bolt threads start at the deck surface, the Shelby stud threads are positioned adjacent to the cylinder bore bottom. This configuration delivers maximum gasket seal and retention while minimizing cylinder bore distortion when the heads are torqued.

Shelby Fe Crankshafts, Dampers and Flywheels

Billet steel crankshafts offer maximum performance durability and are available in strokes up to 4.500 inches. The main journal diameter is standard FE at 2.79 inches, while the rod journals measure 2.200 inches.

In addition, street crankshaft damper spacers are available for billet or factory FE cranks. For street use, a 427-style crank damper features a steel hub bonded to a steel inertia ring. In race applications, an SFI-approved small-diameter unit is offered. Timing marks are etched for accuracy.