- published: 31 Aug 2011
- views: 576573
Overhead camshaft, commonly abbreviated to OHC, is a valvetrain configuration which places the camshaft of an internal combustion engine of the reciprocating type within the cylinder heads ('above' the pistons and combustion chambers) and drives the valves or lifters in a more direct manner compared to overhead valves (OHV) and pushrods.
Compared to OHV pushrod systems with the same number of valves, the reciprocating components of the OHC system are fewer and have a lower overall mass. Though the system that drives the camshafts may be more complex, most engine manufacturers accept that added complexity as a trade-off for better engine performance and greater design flexibility. The fundamental reason for the OHC valvetrain is that it offers an increase in the engine's ability to exchange induction and exhaust gases. (This exchange is sometimes known as 'engine breathing'. ) Another performance advantage is gained as a result of the better optimised port configurations made possible with overhead camshaft designs. With no intrusive pushrods, the overhead camshaft cylinder head design can use straighter ports of more advantageous cross-section and length. The OHC design allows for higher engine speeds than comparable cam-in-block designs, as a result of having lower valvetrain mass. The higher engine speeds thus allowed increases power output for a given torque output.
How do camshafts and valves work? The differences between DOHC, SOHC, and OHV or pushrod valve trains is explained. How the valves are related to each, and how each works. I will also speak of advantages of each of the valve trains. Dual overhead cams (DOHC), singles overhead cams (SOHC), and overhead valves (OHV). Please feel free to rate, comment, and subscribe! And don't forget to check out my Facebook page: http://www.facebook.com/engineeringexplained Also check out my official website: Make suggestions, participate in forums, enter for Car of the Month, learn through logically ordered lessons, read FAQs, and plan your future! http://www.howdoesacarwork.com NEW VIDEOS EVERY WEDNESDAY!
Why are 4 valves per cylinder better than 2 valves per cylinder? Is DOHC better than OHV? 4 valves per cylinder allows for more airflow than 2 valves per cylinder, as there is larger open area when the valves are open. Having a configuration with DOHC and four valves per cylinder means better airflow, especially at high engine speeds, resulting in better top end power. Though it is possible to run 4 valves per cylinder with a pushrod setup (OHV), it's far more common to run 2 valves due to the complication of the packaging requirements associated with a four valve setup. The main advantages of a multi-valve head is that it allows for more airflow through greater coverage, placement of the spark plug in the center of the head for better flame propagation leading to greater efficiency, and ...
DOHC 4 cylinder engine Video - Part 1 A complete overview of the Engine.
DOHC 4 cylinder engine Video - Part 2 A complete overview of the Engine.
DOHC engine work system
Tháo lắp đầu bò _ Quy lát động cơ DOHC 2 trục cam 4 van trên xe ga DOHC (Double Overhead Camshaft) chỉ loại động cơ sử dụng 2 trục cam bố trí trên đỉnh mỗi xi-lanh. Phương án bố trí 4 van cho mỗi xi-lanh tương đối dễ dàng. Động cơ có thể đạt tốc độ vòng quay lớn. Đồng thời cho phép đặt xu-páp ở các vị trí tối ưu tăng khả năng vận hành. Tuy nhiên nhược điểm là trong lượng hệ thống phân phối khí tăng, kết cấu phức tạp, tốn nhiều công suất quay trục cam và giá thành cao. Kênh Video chỉ mang tính chất chia sẻ đam mê không có ý dạy bảo ai hoặc đả kích ai. Các Bạn Subcribe - Đăng ký Cho Channel nha và like hay dislike video để cập nhật thêm clip mới ! THANKS https://www.youtube.com/watch?v=FTU-4xrDO00
2000 civic ex D16y8 with 75.5 wiseco pistons and eagle rods + more mods tuned on hondata S300 + Lenso slicks. Dohc turbo Hatch unknown mods Street race at greatlakes dragaway union grove, wisconsin
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