Cylinder Heads
Minimizing restriction and maximizing airflow in and out of your engine is a necessity for making more horsepower. Installing accessories like a cold air intake, larger carburetor or throttle body, aftermarket intake manifold, headers, and performance exhaust system will provide a considerable increase in power, but that still leaves a major bottleneck - the cylinder heads. Even on performance models, the factory heads can significantly hamper airflow.
Porting cylinder heads to increase port volume, reshape runners, and unshroud valves used to be an art practiced by only a few, at exorbitant prices, and even then results were limited by the material thickness in factory castings. But those days are long gone. As you can see from the large selection on the page before you, today we can supply you with the very latest cylinder head technology for most popular applications, bare and fully assembled.
Although there are many quality performance cast iron cylinder heads, most are made of aluminum. Aluminum heads are much lighter, for an overall improvement in power-to-weight ratio, and lightening the engine can improve vehicle weight distribution. Aluminum also dissipates heat better, and you may be able to run a higher compression ratio without fear of detonation. Regardless of the material, all performance cylinder heads are beefed up in critical areas to allow the ports to be contoured for increased flow in ways that, if attempted on a factory casting, would likely result in grinding into a water jacket.
The design of each cylinder head is the culmination of many hours of flow bench testing to achieve the optimal balance of increased flow and flow velocity. While some cylinder heads are cast with improved ports and runners, we also offer CNC ported heads for the most precise and even flow into and out of each cylinder and the desired surface finish. Performance cylinder heads generally have larger valves but some heads are also available with different valve angles from stock to improve flow, as well as spark plugs relocated in the combustion chamber to improve flame travel and combustion.
Multi-angle and radiused hardened valve seats increase airflow further and valve shrouding in the combustion chamber is minimized to improve airflow around the valve head into the cylinder. Performance cylinder heads generally have manganese bronze valve guides for durability and the heads come already machined with minimal guide height for use with high lift camshafts and large diameter spring seats to accommodate performance valve springs. Screw-in studs and guide plates may be featured on fully assembled OHV cylinder heads along with stainless steel or titanium valves and dual or beehive valve springs.