heating up a little more

What kind of temps are you running at?

With the colder plugs , (ngk 6`s) it ran about 198 - 205, last summer , cooled down to 195-198 on hi way . Never could get the right plug color , was even worse w/ the ngk 7`s I started with , which was recommended as a starting point by hughs engines .
Going to stay with the , 5`s .