So if I am to understanding this right, the larger builds need the higher powers to heat up faster and evenly. If I switch to a rebuildable, if I keep the ohms around 1.5-2ohms I still wont really need a 50w+ device?
No, that's not accurate... First let me direct you to a post that I put up not too long ago...
Clicky Clicky
It might help you understand a little bit, though it's not by any means a direct answer to your original question.
In it's most simple terms... Wattage is a measurement of how much energy we are putting into a device. In this case, our coils, that means it's how much heat we are putting into a device. It's NOT a measurement of temperature... Heat and Temperature are sometimes confused as being the same... But they aren't... If you take a blow torch and put it up to a block of ice, the ice, even right under the blow torch is still going to be 32 degrees... if it wasn't, it wouldn't be ice... It melts on the surface, and that water carries away the heat... but the ice itself remains 32 degrees. So even though we are putting a lot of heat energy into it, the temperature stays the same because the heat is being carried away.
So how much wattage you put into your coil(s) is how much heat or energy you are putting into them... So now we have to think about the other side of the equation, and that's how much heat we can carry away...
When the coil is energized and the wick is supplying liquid (juice) to the coil, that juice turns to vapor. That vapor is then carried away into your mouth and the heat along with it. So the process of vaporization is absorbing the energy being put into the coil and then that energy is being carried away.
So... there are a number of factors that determine how much energy we can put into our system. If we have large coils (rather larger gauge wire or in my preference, larger surface area coils) we distribute that energy over a larger surface area. This means more "contact" with juice which can then absorb that energy while turning into vapor. Then if we have very large air holes and move a lot of air through our system we are able to remove that vapor (and therefore the energy) quickly.
On the other hand, if we have a small tank, say a clearomizer with relatively small coils, small and slow wicking material, and very little air flow, we can't deliver much heat energy into the system because we don't have the means to carry that energy away fast enough.
So you can have one setup with slow wicking medium (let's say silica), small coils and very small air flow that will taste burnt and hot at say 10 watts... On the other hand I can have another setup with very fast wicking medium (let's say rayon), large coils with lots of surface area, and very large air holes that allow massive amounts of air to flow through, and it'll give a very nice cool vape at say 60 watts..
So the ultimate question then comes down to why would you want to make these "improvements" to run higher wattage... Why use fast wicks, large surface area coils, lots of airflow, etc to run high wattage? Because the more energy you can deliver into the system, the more vapor you're going to get out of it. More vapor (assuming it's done right) means more flavor.
Hope that helps!
