Welcome to the second installment in our series on small-block Ford cylinder heads; a look at steel and aluminum castings that are designed for solid street and track performance. As many of you know, street/strip is the parlance that usually describes such pieces (especially for '79-present Mustang loyalists like us). However, since dragstrips aren't the only motorsports venues where late-model Ponies stampede, we begrudgingly acknowledge the fact that "track" is a more-appropriate term for the heads' performance purpose.
Street-specific castings for 5.0-liter/302 engines typically are CNC-ported, include larger valves and upgraded valvetrain hardware, and have improved flow capabilities over stock 5.0 (E7TE, for example) heads. The sampling of street cylinder heads we presented in Part 1 features true bolt-on pieces, that do not require exotic (and oftentimes expensive) supporting hardware or engine modifications, and in some cases, the heads are approved as legal for street use in all 50 states by the California Air Resources Board.
With the street-'Stang bases covered, it's now time to move onto a slightly bigger entity in the Mustang-performance food chain. Cylinder heads we're presenting in this report are geared more toward aggressive-yet-still-streetable 5.0/302 and 351W engine combinations, which usually are power-adder assisted (supercharged, turbocharged, or nitrous injected).
Heads designed for road-and-track-style Mustang engines generally feature larger, sometimes-raised, CNC-opened ports, big valves, and big combustion chambers, which give them the ability to flow much more air than stock heads, or most of the heads that are highlighted in our initial report. Although there are a few heads included in this report that crossover from the "street" category, the heads we're classifying here as street/strip (sorry, we couldn't hold it back any longer) have a lot more intricate nuances than their bolt-on-and-go counterparts, and they really help engines produce the type of big steam (600-plus rear-wheel horses) we really dig.
The heads featured here range in price from $1,200 to $2,500 per pair, and require significant internal and external engine mods (aftermarket pistons, camshafts, intake manifolds, headers, and so on). They typically work well with the higher-displacement, stroker engines such as the 331s, 347s, 393s, and 408s that power many of today's 1,000hp street Mustangs.
Yes, big-steam 'Stangs are a lot more common than they were when the late-model Pony craze took off more than 30 years ago, and as you'll learn through the following photos and captions, advancements made in cylinder-head design definitely are major reasons why this is so.