DartIn the good old days (which weren't really all that good), you always had to be on the lookout for block and cylinder head castings that may have looked good at first glance but suffered from power-robbing core shift. That's no longer a problem when dealing with specialty casting makers like Dart, which inspects every high-end race casting before beginning the machining process.
Dart's Iron Eagle line of cylinder heads have been a part of circle track racing for years, and for good reason: They make power. Standard features on these heads include bronze valve guides, multiangle intake valve seats, and hardened and radiused exhaust seats.
World ProductsWorld Products offers several lines of cylinder heads based on your needs. The S/R and S/R Torquer cylinder heads are designed as stock replacements and are even allowed by many sanctioning bodies for their Limited Stock classes since undamaged original castings are becoming increasingly difficult to find. Of course, World Products says the S/R Torquer cylinder heads offer a 30hp improvement over stock.
The Sportsman II is the next step up and is one of the most popular cylinder heads in stock car racing. World's fast-burn combustion chamber design helps produce another 40 hp over the S/R Torquer line. Finally, there is the Motown Cast Iron, World's attempt at the best as-cast 23-degree Chevy small-block cylinder head that can be made. Large 220cc runners allow it to work best with large displacements or high-rpm engines.
EQ Cylinder HeadsEQ Cylinder Heads may be a new player on the market, but the company already has built a relationship as a sponsor in the IMCA. It also has an extensive lineup of 23-degree Chevy compatible heads. Features include Dura-Bond exhaust seats, a thick deck for angle milling, and a three-angle valve job. They arrive already machined for screw-in valve studs.