what you use non eliquid wise seems to make a difference for me.. I use the 24 american eliquid tobacco menthol vg and don't get much of a throat hit with my 510 cartomizers but get a medium one with V4L cartomizers and I get a really strong one when I use the usb passthroughts with the V4L cartomizers.. So maybe trying some different brands of blank cartomizers may help perhaps and a passthrough if you don't have ones..
Will the V4L cartos work on my 510?