Plug ??

Run NGK V-power, IMO they are one of the best for reading, with that compression, i would start out with a -7 on the heat range, i ran -6s with 10.3.1, just remember that with the NGKs the higher the #, the colder the plug, its vise-versa, so a -5 is hotter then a -6. A buddy of mine had a similar combo in his dart (440/906s/.590 cam/12.5 comp.) & ran -8 at the track.