[anime ronin]

well of course with the gears luffy has gotten stronger. but overall luffy is really just a guy with c ontinuous dominant strength. it never really changes as far as power goes except when he uses his gears. notice when he fights bosses, power is really never the problem for him, its typically how he beats them. like he always has to do something different to beat his opponents rather than use more strength.

so in dbz talk, his power level is pretty much the same throughout the series...