1991 Ford Explorer 91 ford engines,

First, we always recommend staying with a direct fit part to avoid problems. However, I will say if both are the same size engine, it should fit. I will tell you that you will need to switch anything that is different from one engine to the other. For example, the sensors may be different. Check and compare both engines to see if they are the same with the sensors in the same places, the intake is the same...