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Ford Performance Boss Block 347ci 450HP Rear Sump Crate Engine

Item 50191
AmericanMuscle no longer carries the Ford Performance Boss Block 347ci 450HP Rear Sump Crate Engine. Please check out 2015-2022 Mustang Crate Engines and Blocks for an updated selection.
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    Product Information

    Features, Description, Q&A


    • 347 cubic inche crate engine
    • Boss 4-bolt main block
    • 9.7:1 Compression ratio (nominal)
    • 450 hp @ 6000 rpm, 400 lb.-ft. @ 4900 rpm
    • Forged steel crankshaft, forged pistons and forged steel cap screw connecting rods
    • Rear sump pan fits most Fox body cars
    • Perfect for kit cars, street rods, Mustangs and Fox-bodied cars


    Naturally Aspirated. Built with forged pistons and a Boss 4-bolt main block this Ford Racing 347ci crate engine makes 450 hp at 6000 RPM (with headers, and a 650 CFM Holley carburetor not included). This crate engine features a 9.7:1 compression ratio and a High-performance rear T-sump oil pan making it perfect for Naturally Aspirated applications.

    Built Ford Tough. This Ford Racing crate engine is built with a Boss 4-bolt main block and features forged pistons, aluminum Ford Racing "Z" cylinder heads, and a hydraulic roller camshaft with roller rocker arms. Additional features include forged steel cap screw connecting rods, forged steel crankshaft, double roller timing chain, MSD billet distributor and single plane Victor Jr. intake manifold.

    Rear Sump. This Ford Racing engine features a rear T-sump performance oil pan and pickup, regular rotation timing cover and regular rotation water pump, and non-EFI valve covers.

    Application. This Ford Racing 347 Cubic Inch Crate Engine is the perfect upgrade for any Fox-bodied based Mustang, kit car, street rod, resto-mod, or Fox-bodied based car.

    Technical Note. The included flywheel (M-6375-A302B) should work for most 157-tooth manual transmission applications. For other transmission applications use the proper 28 oz. flywheel. Firing order 1-3-7-2-6-5-4-8 (5.0L HO and 351W order).

    NOTE: Ships Continental 48 States ONLY. No Canada, APO/FPO, Hawaii, Alaska, Puerto Rico, Guam or Us Virgin Islands.

    If shipping to a business, please include the business name. Also, after your order is placed, be prepared to let us know if you will need a Lift-Gate service. You will be contacted via email before your order ships.

    CA Residents: WARNING: Cancer and Reproductive Harm -

    Installation & What's in the Box

    Installation Info

    Questions & Answers

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