Set-up help needed

[Jamie.T]

Ive set my x-6 squared up to the X-factory UK std set-up on associated threaded shocks.

Ive fitted blue springs on front with 35 weight and
silver springs on rear with 27.5 weight.

The back feels extremely soft in comparison to the front which feels quite hard. Does this normal or have i done something wrong? Will be running the car indoor on a medium grip carpet track with yellow spikes.

Thanks in advance

Jamie.....