There are several types of hatch lifts.
With spoiler...With spoiler and rear wiper...With with wiper but no spoiler...no wiper or spoiler...You get the idea.
Each lift has a difference weight rating. Installing a lift designed to lift the extra weight of a spoiler and wiper on a "non" hatch will cause the hatch to lift quicker and with more force.
I installed new lifts (with spoiler) on my 89 with came with a 3-piece spoiler. It opens very quick. I may have to change to a non spoiler lift later on.