Spark plug gap and torque

Does anyone know what the gap should be on spark plugs for the 197?

Also, what torque should be applied to them?
 
It's just that i've had a slight ticking noise on idle since changing the plugs. They're standard ngk platinum plugs and the gap did look slightly different to the standard ones i removed
 
if you buy the right ones they come pre-gapped - as for torque - i do it by "feel"/experience

the "tick" could be because they arent tight enough - if you look on the ngk website or champion it will give
you a guide on plug torque tightening - just depnds if they have a washer or are taper plugs
 
Thanks, have just checked NGK website and it specifies 30Nm. I've retightened the spark plugs and still have this ticking noise