unloader relay

[R&D man]

I am currently doing my wire harness and was wondering if the unloader relay is used .
the car is 325es 1986 .the engine being transplanted is, m50 with vanos

[RoadHazard]

Which one are you talking about? Not sure if it's the same for 86 but in 89, there are 2 unloader relays in the E30 fuse box. Those are K5 and K7. K5 is for power windows. K7 is mainly for the HVAC stuff and the outside rear view mirrors. So, your car will run without them but they're recommended to have.