Yep, that's about right, maybe a little more. The only scale I've had to use is an old one I found in the shed that would melt if you sprayed it down with WD40, so I'm betting it's not completely accurate.

I have it at 18/38 right now and can run without the fans. I tried the 20/36 set up I have on hand but it seemed to get a little hotter so I went back to the 18/38. I"ll eventually get the fans fitted so I can gear a little higher, the 20/36 was INSANE for the couple of battery packs I ran it.