No, a temp guage is not for tuning. For me, it is just a little helper to give you piece of mind. In other words, I can do a lot of experimenting with tuning and if my temp is OK, I'm not going to ruin my engine. I learned to tune by making changes and then watching/listening compared to performance. Doesn't take long to figure out the "if/then." With no temp guage, I don't think I would have been as aggressive with my experiments. It's a good learning tool.