How fast do they go up by themselves?Well depends on the temperature,weight and power of gas springs.My doors are a bit heavier becuse of the insulation for my stereo and a bit heaver speaker so l have to help them.But lt's not hard at all,lt's the same thing as opening the hood or hatch.
This time l've done the same thing but with my girlfriends car on the passanger side door. l'm not that fast on this one lol and her doors shoot strong upwards and l have to hold them down strong!