On a related note, I currently have thumper E7 heads and stock intake with tmoss ported lower. Dyno'd at around 300fwhp.
Would a cobra intake likely show much improvement? Enough for the cost?
Not a lot, your intake flows ~190-195cfm and the Cobra flows ~200-205cfm. It takes ~1.5 cfm to make 1HP, so MAYBE 10 HP tops. Gonna be hard to feel in the butt-o-meter. Mike's E7 heads flow a little overe 210cfm peak.