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Hi!
I am just wondering what is the different between SOCH and DOHC? Which one is zetech engine? Anyone can tell me? Thanks
 

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I change diapers now
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SOHC = Single overhead camshaft
DOHC = Dual overhead camshafts

SPI = SOHC
Zetec = DOHC



- Drew
 

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Soch is the engine that has olny one camshaft overhead.Dohc is the ZETEC engine and has two overhead camshafts.Ovearhead means that the cams arre in the top of the engine.Also another difference is the Zetec(DOHC) has 16 valves.The sohc has 8 valves.
 

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I know the diff. between SOHC and DOHC(duh..)But would DOHC mean it had 2 cams per head or for the whole engine? I think a new GT is SOHC, so is it pushrod or does it have one cam per head?
 

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its not a pushrod, their all modular motors. the mustang gt has 1 cam per bank (a side). whereas the cobras have 2 aside, or what the older fellas would call a 'cammer' or 4-cam.

not all dohc engines have 2 cam sprockets, my old celica ST has a 3sfe DOHC engine, but w/the FE head, it used only 1 sprocket, whereas the 3sGE engine in the GTS, almost same bottom end w/different head was DOHC, same 16valves, but different head design that used 2 sprockets.

-Ult
 

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Comparing DOHC and SOHC is like comparing chocolate and.............

j/k
 

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Originally posted by Hi-Risk:
Comparing DOHC and SOHC is like comparing chocolate and.............

j/k
<font size="2" face="Verdana, Arial">Not always the case. Subaru engines are weird in general but in 1999 the DOHC head on 2.5L was changed to a SOHC. They got better peak and overall performance from the SOHC.
 

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with a SOHC engine you have one cam that has lobes on it to open both the intake and exhaust valves.

With a DOHC the intake valves have a cam to control them and the exhaust have a cam to control them. Because they are separate, you can control the timing of the valve opening and closing better for the best performance and also you don't have to place your valves in the cylinder head so they are close or angled towards the intake cam so they can be angled for better performance.

DOHC is better if it can be done because of the better control and they are typically a higher-rpm motor, like the DOHC 4.6 in the Mustang Cobra.

Hope that helps.
 
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