From experience, Torkoal is always running 0 Spe IVs, purely because of the MU against Trick room. If you are making a venukoal team, chances are that you're also running some form of Trick Room with the t eam, as torkoal is a trick room staple, and it can work quite well out of trick room, as it has decent bulk, letting it take quite a bit of hits. Usually, what I do with venukoal is I have my TR 'mon, the setter, either a redirector or the second Trick Room 'mon, and venusaur. So, when TR is over, you bring in venusaur, and then, you can wreak havoc sleeping and destroying things. Therefore, I would say that you should run Torkoal with a quiet nature and 0 spe IVs.
Now, you might not believe me, so here are some top players' venukoal teams :)
https://pokepast.es/74cd7d6f310f31d1
https://pokepast.es/720fb726f90e36df
https://pokepast.es/55000a8487b7ff8e
https://pokepast.es/b15347c4ac46a6ea (technically 8 Spe Ivs, but that's still basically 0)
https://pokepast.es/7d1d0f433f14d4d9
Source for the teams: Victory Road VGC