I have interchanged them and it seems to work.
Everything is the same apart from the hex wrench. The hex on the RN12YC is 13/16" (20.6mm) and on the RC12YC it is 5/8" (16mm).
yes
I was wondering the same thing this afternoon
GAP .030"
RN11YC can also use RN12YC
Harley-Davidson uses .040" gap in their engines using this plug.
no
Yes
Rc12yc
your dum
depends how long you leave them in the freezer. The best I can remember, the 5R6A is the colder of the two.
A champion RC12YC spark plug is 14mm thread diameter. The torque for this size is 18-22 foot-pounds (25 to 30Neuton·meters)
yes
0.035 inch gap using Champion RN12YC Spark Plugs