Ad
related to: best budget heads for sbc valve repair diagram 2 phase pump
Search results
Results From The WOW.Com Content Network
In sidevalve engines the head is a simple plate of metal containing the spark plugs and possibly heat dissipation fins. In more modern overhead valve and overhead camshaft engines, the head is a more complicated metal block that also contains the inlet and exhaust passages, and often coolant passages, Valvetrain components, and fuel injectors.
A mold of the suboptimally designed ports of a Ford two-liter head for use in Formula 2000 racing. It is shown as manufactured with the intake port on the right. The Ford two-liter F2000 engine in stock trim equipped with the head shown above was capable of delivering 115 horsepower at 5500 rpm for a BMEP of 136 psi.
This happens because the 2 cylinders which share the port are not equally spaced in terms of firing order. For example, the Leyland Mini with its 1-3-4-2 firing order has the 1 and 2 inlets siamesed and the 3 and 4 inlets siamesed. First the number 3 sucks the mixture out of the port, then there is less left for number 4.
A crossflow head gives better performance than a Reverse-flow cylinder head (though not as good as a uniflow), but the popular explanation put forward for this — that the gases do not have to change direction and hence are moved into and out of the cylinder more efficiently — is a simplification since there is no continuous flow because of valve opening and closing.
In the 1980s, many U.S. production engine remanufacturers began reaming valve guides, rather than replacing them, as part of their remanufacturing process. They found that by reaming all the valve guides in a head to one standard size (typically 0.008 in. diametrically oversized), and installing remanufactured engine valves having stems that are also oversized, a typical engine head can be ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
One of the first practical VVT systems used a variator to change the phase [note 1] of the camshaft and valves. This simple system cannot change the duration of the valve opening, or their lift. [note 2] Later VVT systems, such as the helical camshaft or the movable fulcrum systems, could change these factors too. Despite this limitation, the ...
Discover the latest breaking news in the U.S. and around the world — politics, weather, entertainment, lifestyle, finance, sports and much more.