<tech> DOHC vs. SOHC

[Christopher Pawlowicz <chrisp@xxxxxxxxxxxxxxx>]

KC asks
>What's the advantage of having two cams versus one?  I can see an
>advantage with VANOS on one or both (more leeway for adjustment).  Is
>there anything else that two cams do better than one?
>

don't you *have* to have 2 cams to work a multi valve engine ?

if you have 2 valves per cylinder they can be side by side (in the same
direction as cylinders) and 1 cam can operate both valves..

but if you want 3 or 4 (or more?) valves per cylinder you have 
a cluster of 4, and 2 can be operated from one side, but the other
two have to be operated from the other side of the bank of cylinders
which means another cam

is there such a thing as a sohc multivalve engine ?


chris pawlowicz
'89 325i
'74 2002

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