Just another question in my random attempts at making a totally mental Cacturne. What speed evs would an adamant natured Cacturne need to outspeed an adamant Swampert with an adamant nature itself and no speed evs? Or any non speed boosting natured base 60 Pokemon with no speed evs, really.
Also, I need to ask the same question for a Swampert with 44 and 84 speed evs with an adamant nature, too. I'm sticking with an adamant Cacturne, so if it's not possible to outspeed 84 speed evs on a base 60, that would be kinda key.
With the natures listed by you(adamant) Cacturne would need a minimum of 46 EVs in speed to outspeed Swampert.
For the EVs Swampert has in speed (starting with 44) you will need 88 EVs for Cacturne, and 84 EVs in Swampert, you will need 128 EVs for Cacturne.
I did all the calculating with the Showdown teambuilder.