I recommend switching output to watts and tuning in from there. coils often vary from what it says on the box. I think your mod can check resistance.
Each person has their own sweet spot but avoiding burning is pretty important. Once you burn a coil enough it never comes back.
Watts simplify that. In general, a 7 watt vape on a 1.8ohm coil should be about the same as a 2.0, 2.2, etc.
Well said Bill. Watts are a bit more controllable, when I am using my dna20 I am normally around 10-11.5 watts.
Yes, the SVD can check resistance, just hold the up and down buttons. And yes, expect the resistance to vary slightly from the number on the box.
When you burn the coil (a misnomer) you are actually burning the silica that is used for wicking. The kanthal/nichrome used to make the coil won't burn until around 1500° F.
As for the reason you were upping the power, I can only guess you wanted more vapor, in that case... get a lower resistance coil or a tank with dual coils. As mentioned above, the nautilus by Aspire is a nice tank, pyrex tank to no cracking (unless you drop it, lol) and dual coils with airflow control. Also, get in touch with me in some of the rebuilding threads (and the Pif - Still Smoking thread) if you want some more help with the t3s or are ready to try something like a Kayfun that gives you more control over your vape.
As to the sweet spot... if you find it, great! Don't try guessing how to match it on other devices, just Google "Sweet Spot Calculator" and follow the instructions. Makes it dead easy.
Happy vaping!