Ford Cylinder Heads
Air Flow Research
Air Flow Research (AFR) are relatively new entrants into the Small block ford cylinder head market. They produce extremely high quality CNC machined aluminium heads in 165, 185, 205 and 225cc intake runner variants. Widely regarded as one of the current market leaders AFR heads are responsible for some very powerful SBF engines. Retaining stock valve train geometry and requiring no finishing work out of the box AFR's are often regarded by bolt-on racers as being some of the simplest bolt on HP that money can buy.
Source: Air Flow Research
TrickFlow - Twisted Wedge Heads
TrickFlow Twisted Wedge Heads, somewhat like the AFRs mentioned previously are also relatively recent entries in the SBF market. They are widely seen as direct competitors for AFR in both price and performance.
From their site: "Twisted Wedge heads feature an exclusive combustion chamber design.The patented 61cc chambers feature rotated intake and exhaust valves moved over the center of the cylinder bores. As a result of optimizing the valve locations, valve angles, and combustion chamber shape, the Twisted Wedge heads use stock height exhaust ports without power loss."
Source: TrickFlow
RHS - Racing Head Service Heads
RHS is the newest major entrant into the SBF cylinder head market. Originally a New Zealand based company (called Pro-Topline), RHS has recently been bought out by Comp Performance Group (makers of comp cams). RHS has a very broad range of heads available finished, unfinished, in aluminium and cast iron. This is unusual as the majority of performance brands focus solely on aluminium products. RHS flow numbers indicate performance on par with the premium SBF heads at a significantly lower price.
Source: Racing Head Service
Edelbrock
Edelbrock is one of the most established players in producing aftermarket v8 components. It has a broad range of products and packages aimed at different performance levels and budgets.
Source: Edelbrock
CHI - Cylinder Head Innovations
CHI are suppliers of fantastic Cleveland aftermarket aluminium heads that are designed and manufactured in Australia. The CHI heads can be used on windsor motors to build potent clevors or boss 302 motors
This is what CHI have to say about their heads:
"Our world renowned 3V heads have set the benchmark by which all other Cleveland heads are judged. Combining the very best attributes of the 4V head, and with the air speed of its smaller counterpart the 2V head, they have no equal in performance when combined with our matching Engine Masters Series manifolds."
Source: CHI