Another thread for everyone to learn. Please lets share meaningful information.

uboma: Another thread for everyone to learn. Please lets share meaningful information.

DOHC is a type of engine/cam design DOHC means Double Over Head Cam (where two Cams placed over head operate the various valves both intake and out take/exhaust valves). Now there are 2 camshafts per header. So in an inline there are 2 camshafts because there is only one header, but there is 4 in a V-type or flat engine. These DOHC engines usually have 4 valves. One camshaft for the exhaust valves and the other for the intake valves



SOHC means Single Over Head Cam (Only a single cam rod operates the intake and out take valves). That means that there is only one camshaft per header. Inline engines will contain one camshaft. V-type and/or flat will contain 2 camshafts. For a SOHC engine there are usually 2 valves per cylinder but there can be more with the addition of cams for each valve.



When you compare their performance you discover that SOHC engines develops a little less power than its DOHC brother, but it develops more of its power earlier and is therefore more flexible and generally more economical. The DOHCs rev much harder and higher, and at mid to top revs develop much more power for the same displacement engine, making them ideal for racing or performance vehicles. And if the DOHC is a V-engine, like a V6 or V8, it could be called a Quad-cam.

SOHC engines are cheaper and less complicated to design, build and maintain because of the lesser moving parts, while DOHC are more complex to design build and repair because of the extra moving parts.

Another advantage of having a DOHC engine over a SOHC is that the engine has twice as many intake and exhaust valves as a SOHC motor. This makes the engine run cooler and more smoothly, quietly, and efficiently. But the downfall is that DOHC engines cost more for repairs.

REFERENCE:
1. My brain (my experiences plus automotive studies).

2. http://www.quadcrazy.com/atvforum/general-atv-discussion/7364-whats-difference-between-dohc-sohc-motor.html

Is there a label diagram to view on this topic

lomomike:

DOHC is a type of engine/cam design DOHC means Double Over Head Cam (where two Cams placed over head operate the various valves both intake and out take/exhaust valves). Now there are 2 camshafts per header. So in an inline there are 2 camshafts because there is only one header, but there is 4 in a V-type or flat engine. These DOHC engines usually have 4 valves. One camshaft for the exhaust valves and the other for the intake valves



SOHC means Single Over Head Cam (Only a single cam rod operates the intake and out take valves). That means that there is only one camshaft per header. Inline engines will contain one camshaft. V-type and/or flat will contain 2 camshafts. For a SOHC engine there are usually 2 valves per cylinder but there can be more with the addition of cams for each valve.



When you compare their performance you discover that SOHC engines develops a little less power than its DOHC brother, but it develops more of its power earlier and is therefore more flexible and generally more economical. The DOHCs rev much harder and higher, and at mid to top revs develop much more power for the same displacement engine, making them ideal for racing or performance vehicles. And if the DOHC is a V-engine, like a V6 or V8, it could be called a Quad-cam.

SOHC engines are cheaper and less complicated to design, build and maintain because of the lesser moving parts, while DOHC are more complex to design build and repair because of the extra moving parts.

Another advantage of having a DOHC engine over a SOHC is that the engine has twice as many intake and exhaust valves as a SOHC motor. This makes the engine run cooler and more smoothly, quietly, and efficiently. But the downfall is that DOHC engines cost more for repairs.

REFERENCE:
1. My brain (my experiences plus automotive studies).

2. http://www.quadcrazy.com/atvforum/general-atv-discussion/7364-whats-difference-between-dohc-sohc-motor.html

Nothing more to add. Well explained.