Various possibilites:
- Have you tried dripping e-liquid (3-4 drops) directly on the atomizer bridge (i.e., down that long tube)?
- Perhaps the 510-to-801 adapter is faulty. I've never worked it in that direction, but I have had a couple 901-to-510 adapters that let me down.
- Perhaps the 801 atomizers are faulty or at least the one(s) you've tried.
- A regular resistance 801 atomizer is ~3.5 ohms: a heck of a lot higher than the 510's 2.3 ohms. The eGO/Tornado (and the other fat batts) are high mAh, but fairly low voltage: ~3.3V: not really strong enough to drive that atty effectively: 3 watts. Pretty wimpy. Perhaps if you draw really, really hard, you might see a little vapor.
- '801' is derived from the DSE801 penstyle model, but (like kleenex) is often used to stand for any penstyle atomizer, e.g., Joye302, BE112, RN4072, M201. The M201 atty is not compatible with the others' batteries (or adapters). But even the others are not 100% compatible with each other. What model are your '801's? [If they have a red devil's head on them (i.e., from Totally Wicked), I think they are not DSE801; they're described as "801 compatible." Doesn't mean they're bad, just might explain compatiblity issues.]
[NOTE: If you got the adapter and attys from TW (where, I assume, you also got your Tornado), why not write to them about this problem?]
I hope that one or more of these speculations gets to the root of your problem ... or, at least, the explanation for it. However, in most of those cases, your current equipment is inadequate to the task at hand.
- The least expensive solution would be to buy a regular penstyle battery, ideally of the same model. This page of Version 2 of the WWV lists/links many suppliers of those models. These are higher voltage then the Tornado, but still not true 3.7V. Perhaps ~3.5V: 3.5 watts vaping.
- A better solution would be to use those "801" atomizers (assuming they are not the problem) on a mod of at least 3.7V, such as the SparkPlug (no adapter needed), currently on sale for $40 (complete kit). 3.9 watts vaping.
- If you don't mind being tethered, an even better (and less expensive) solution would be a 5V 801 passthrough, $11 from LiteCigUSA or $13 from VaporKings. [NOTE: LiteCigUSA's website doesn't specify 5V, but since there is no inline battery, I assume that it is.] 7 watts vaping: Sweet spot!
