Scott bikes are known for being notoriously weight-weenied and not having much accommodation or intent for heavier stuff, like Hope E4 calipers. Although this varies widely by the user, the E4s are kind off "enduro" brakes. I think they are lacking power for that designation, compared to other brands, but whatever, they are pretty beefy calipers and best used with pretty beefy rotors, at least 180. If you are on 160 rotors I don't see any benefit from a bigger caliper and smaller rotor, it's the opposite of that which would give you better rear-brake heat dissipation. Any time you have one of those setups with the caliper in-between the seat and chain stays you should probably plan on 2-piston calipers, not 4. I have one fat-bike that has that configuration and it's definitely limited in that area, space is tight. I'd suggest going with an X2 rear caliper if you want to keep Hope. Higher chance of fitting. What rotor size are you using BTW? If you are direct mount/no adapter I'd assume 160?