While 427 Cobras are typically known for their big-block power, in recent years stroked small-block engines have become popular in various replicas. A small-block V-8 with big-block displacement is not only lighter, but also costs less for a similar output.

Taking that trend to an even greater extreme is World Products’ new 454ci small-block. Introducing a new engine block with big power potential is an endeavor not for the faint of heart, though. Consider the time and effort invested in its creation, along with the enormity of the engineering details and hundreds of complex regions of a new casting.

But that’s what World Products unveiled recently: two innovative Ford-based blocks. They are both defined as small-blocks and are distinguished mainly by their deck heights: one measures 8.2 inches, and the other 9.5 inches.

The latter sports a displacement of 454 cu in (7.4L), plus a host of other advantages. Called the Man O’ War, this moniker was used on a previous block design, but when World Products was sold in late 2012, the new owners decided to entirely revise it.

Now boasting new architecture, it’s the brainchild of World’s Engineering Director, Dick Boyer. The design accommodates the original 10-bolt cylinder heads, as well as the latest aftermarket high-performance 18-bolt counterparts. Introducing six head-bolts per cylinder, combined with extra thick decks, greatly reinforces gasket clamping. 

In addition, Boyer, an accomplished race engine builder and tuner, sought to enhance the strength and ruggedness of the new Man O’ War. To do so, he cast the new power unit in a 40,000psi iron alloy, and also increased the thickness of the main bearing webs, upgrading the front one by adding 0.080 inches and the center three by 0.030 inches. To increase the main web structure further, the traditional 1/2-inch main cap fasteners were revised to 7/16 inches, leaving more material in the webs.

A replacement for both Ford’s 302 and the ubiquitous Windsor motor, World’s new block is therefore available in two deck heights: 8.200 and 9.500 inches respectively. Deck heights have a direct bearing on the engine’s capacity. Shorter deck heights limit the stroke length and hence the engine’s cubic inch displacement.

The 8.200-inch block is a direct replacement for 5.0L Mustangs and is compatible with OEM heads and exhaust systems. The 9.500-inch block works with all 351 Windsor-style components. Both employ Siamese cylinder bores with thick walls, which can be bored to 4.200in.

Also, the bottom of the cylinder barrels are extended down into the crankcase by 0.500 inches. This approach is designed to provide superior piston support while operating with long-stroke crankshafts. In the case of the 8.200-inch deck blocks, clearance is provided for a 3.500-inch stroke crank, while the 9.500-inch deck blocks accommodate a 4.250-inch stroke crank.

Either billet steel or nodular iron main caps are fitted. Featuring a splayed 4-bolt stepped and doweled register they incorporate ARP fasteners (bolts are used with the nodular caps, studs with the billet caps). In addition, priority-mains oiling system is featured, which delivers oil to the main bearings first, ensuring reliable lubrication at high rpm. To further improve main bearing lubrication prospects, the inadequacy of restrictive oil flow was overcome by enlarging the diameter of the main oil gallery and also the passage from the oil filter to the main gallery. 

Boyer’s ingenuity lies not only in combining 4.125-inch bore with 4.250-inch stroke, ensuring the engine would accommodate many off-the-shelf parts, but also in making it available as a complete package. An entire kit of compatible components engineered and tested and proven simplifies construction, shortens build time and suppresses rising costs. Pushrods, for example, are supplied to the exact length and specification—so is everything else.

Introduced in 1962 by Ford as their engine replacement for the Y-block, the early Windsor’s rated power and torque values of were stated as 145hp at 4400rpm and 216 lb/ft at 2200 rpm. As it evolved over the next 40 years it arguably became Ford’s most successful competition engine.

Now revitalized for 2015 in 454 cu in configuration, Boyer has brought a fresh engineering to the design. By combining the new block with World’s standard kit of parts, he generated an engine that delivers as much as 735 horses.

Finally, the blocks are semi-finished to 0.005 inches undersize to accommodate 4-inch and 4.125-inch piston and ring packs.