First of all, the device your looking for to suit ALL your needs is the Thermovape Cera (im a proud owner of the EO and LL cart and its a MAJOR improvement compared to the 1st gen TET products, though I still keep my 6v and HP core on hand for rainy days or back up. But ill help ya out with getting that EVO working substantially better
Ok well if your looking to do concentrates its depends on what form and kind of concentrate (i.e. wax, qwiso, reclaim..etc..)
I succesffully vaped that dark gooey oil known as qwiso (though mine were really the remnants of everclear tinctures)
Steps;
1. place a smaller screen in the bottom of the evo to prevent oil clogging your core(cut a regular screen down to the same size as the barrel of your EVO)
2.Bend a 2nd metal pipe screen where the edges fold inwards like a little bowl shape or cone.
3. Warm up your EVO for a good 30-60 seconds. (Until the handle is warm should be ideal)
4. Put your oil in the little basket you made using your metal screen and try to for the best ball shape you can.
5. Hold the switch the WHOLE TIME, dont let off the switch even between hits, just take very long steady drags, each hit will gradually be a little larger so dont be discouraged by the wimpy first few.
PS. Might do you some good to go back a few pages and observe the pictures of how I set up my EVO (Whip attachment and airflow control using a small handkerchief) This set up almost double my satisfaction of the device just using simple materials laying around my house. A whip,(from my asthma nebulizer tube) and microfiber eyeglass cloth held on by a twisty tie.