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Chevrolet Script Valve Covers

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Version two received the same Hedman headers and Flowmaster mufflers used in version one, but we added an Edelbrock Performer RPM manifold and 850 Holley double-pumper. We also slid on a set of GM Performance Parts cast-aluminum Chevrolet-script valve covers. We switched MaxJet jets in the Holley until we achieved the best power with 91s in all four corners and 32 degrees of total timing. This combination produced peaks of 501.3 hp at 5,500 rpm and 565.5 lb-ft of torque at 3,250, and it still idled under 900 rpm.