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Ford Motorsport 351-HO SVO Small-Block Engine
Big Cam, Big Heads Equal Big Top-End Power
Ford's top ante in the high-stakes game of small-block crate engines is its 385hp 351-HO SVO (PN M-6007-A351). The Dearborn boys haven't offered an engine nearly this powerful since the demise of the big-block Cobra Jet and 351 Boss engines. Every engine is test-fired and comes complete, less air cleaner, carburetor, headers, ignition module, spark-plug wires, or accessory drives. The developmental prototype met Ford's standard durability dyno torture test: 50 hours running at peak torque, followed by 50 hours running at peak horsepower.
Built around Ford's marine 351W two-bolt-main block, the bottom end includes a nodular cast-iron crankshaft; heavy-duty marine/truck connecting rods, and hypereutectic pistons with a 1/16-inch moly-faced top ring, 1/16-inch chrome-plated second, and a 3/16-inch standard-tension, expanded rail-type oil ring.
The engines flat-tappet, high-lift hydraulic cam offers a significant power increase without beating up the valvetrain. Because the cam is designed for maximum horsepower, only eight inches of vacuum are present at idle. For street use, we'd recommend a vacuum reserve canister. Automatic-trans applications require a minimum 2,500-stall converter.
The cam's lobes activate anti-pump-up hydraulic lifters; hardened 5/16-inch-diameter pushrods; and 1.60:1 roller tip, needle-bearing-fulcrum roller rocker arms to lift the 1.94-inch intake/1.60-inch stainless steel exhaust valves off their seats in SVO Windsor high-flow aluminum cylinder heads (PN M-6049-J302), which feature minor porting under the valve seat in the short-turn-radius area and a three-angle valve job.
Induction is handled by Edelbrock's 351W Victor Jr. A high-rise, single-plane intake manifold optimized for top-end horsepower, it accepts standard 4V Holley carbs (750- or 780-cfm sizes recommended). A Ford electronic distributor, an SVO steel-billet 157-tooth manual-trans flywheel drilled to accept either 10-½-inch Long or diaphragm clutches, an SFI spec 18-1 damper, and an aluminum water pump complete the assembly.
The entire engine carries a $4,450 retail price, which is several hundred bucks off the list, and which you can find by shopping around. Like all Ford Motorsport parts, the engine is guaranteed against parts or assembly defects, but it carries no warranty. We'd recommend this engine for serious weekend warriors and ultrahigh-perf street machines. For heavier cars and/or milder applications, Ford offers the $3,395 351 GT-40 SVO assembly (PN M-6007-B351), which comes with cast-iron heads and an auto-trans flexplate. Using SVO's dual-plane intake (PN M-9424-Z351), a 750-cfm Holley, and headers, it's still rated at 346 hp and 364 lb-ft.