i weigh 92 lbs. tried to partial with a very thin backpack strap type "rope." it cut off my circulation slowly, i could still breathe but i could feel the blood roaring in my ears & the pressure building in my head. my survival instinct kicked in & i fought to escape. i was probably hanging for only a minute.
any rope would kill you but i'd go for a thicker one - all you need to do is position your neck artery correctly & apply pressure. rope shouldn't matter as long as it's tied to something that can hold your weight. remember to slip knot not noose.
i hope this helped.