i was just wondering what the difference and pros and cons between a sohc and dohc? thanks

 

hell if i know

 

With a dohc you can eliminate the rockers and if you want to play around with cam timing you can change one (intake or exhaust) and not the other.

 

Not absolutely sure but the DOHC motors dont usually use rocker-arms to move the valves. The cam lobes effectively ride right on top of the valve stems. This makes the action to push the valve more efficient and less power lost moving mechanical rocker arms. Overall, it makes for a more efficient process.

I think ? If i'm wrong, please educate me !!

 

are there any advantages then of a single?

 

Less cost to replace or upgrade.

 

To my understanding, an sohc has slightly less cam-drag than a dohc. the difference comes from the sohc running all valves from one cam but making up power by the extra leverage on the valves provided by the rocker arms. The DOHC lacks the leverage of the absent rocker arms. However, with the leverage provided by the large cam sprockets, any difference in power is minimal and virtually undetectable. As far as a difference in power, there is virtually no discernable variance. This is how I have come to understand it at least.

~HoundDog

 

The double cam units that eliminate rockers are much more efficient. It eliminates two wear spots, two noise making actions, (the rocker arm fulcrum and rocker arm-to-valve tip connection). That rocker arm swinging back and forth takes energy, energy better spent moving tires. Eliminating moving parts is always a good thing. And, the cam lobe over bucket on valve much less likely to get out of adjustment. Although granted a single cam/rocker arrangement you only need to drive one cam, but that one cam still needs to actuate all the valves via rockers. My $.02.

 

The purpose of DOHC is so you can arrange the valves better and not be limited by the rockers in your valve placment.

 

so would i be correct in saying one is not better than the other, just a different way of building engines? thanks for the replies and knowledge!