What are you running for a motor.If you are running a weadge head don't try the 2 tread down as agood heat.I have been there! The max setting we found would show heat all the way aroud the top of the plug. If it's starting down to the treads get some more fuel in.Again this is on weadge head. Hemi is a whole diferent deal. Then the two thread deal is good.We backed my motor to where it was 3/4 around the plug.If you use top end lube it will make it harder to read also.There is a good article on dragstuff by mike canter about reading alcohol plugs.