will a clutch for a DOHC fit a SOHC engine?
 

like the one here... http://cgi.ebay.com/ebaymotors/ws/eB...spagename=WDVW

NO they will not interchange.

alright

I heard that you can do it if you use the right flywheel.
SOHC flywheel and clutch will work on DOHC
DOHC flywheel and clutch will work on SOHC
I have heard of some MX3 guys who have done it.

swapping out the flywheel will allow you to use the dohc clutch kit (any flywheel from a mazda 1.8 DOHC, Protege and Escort GT) but the friction plate will not fit the intermediate input shaft for the SOHC tranny, you need to use the friction plate for the SOHC (I'm not sure, however, if the tranny input shaft will work with the DOHC pilot bearing or even if you can use the SOHC pilot bearing with the DOHC flywheel.

Doing this will allow you to get a clutch kit with a greater clamping force (I've seen 90% increase with centerforce and 110% increase with another brand) but if your engine is stock the 30% increase given by centerforce's SOHC clutch kit would be sufficient for hard driving.

You could also do the DOHC tranny swap easily if you get the matching flywheel and clutch kit but the gear ratios would probably be too steep for your underpowered SOHC engine (you' would be surprised how much of a difference 20 horsepower makes:-)