how can you tell the difference between a SOHC and DOHC engine?
 

i have a F20A (Japanese) engine in my 1991 honda accord and i dont know if i have a SOHC or DOHC cause they made this engine in both styles.

Just look at the way the head is shaped, if it's shaped tall and skinny like this:http://www.808speedshop.com/images/c...-c.jpgIt's a SOHCIf it's flat and wider, like this:http://got-jdm.com/images/b16a2_nice.jpgIt's a DOHCIf you e-mail me a picture I can tell you right away. You can also take the timing belt cover off and see if there's one or two cam gears. The JDM F20A did come in a DOHC and SOHC like you stated, much like the JDM ZC motor. So the only way to tell is to know what each looks like, and look at it.