Brushless help please

[Feight]

Hi, I'm another noob to the world of brushless rc.

I had the crazy idea of converting a hyper 7 and I'm now at the point of just needing to work out what motor would be best.

I've read round and I'm having one hell of a job working out what would be best.
I was planning on 3s because the shell doesn't offer tardis like properties and 4s might be like trying to get a wardrobe in the back of a fiesta (not impossible, but requires some seriously creative thinking)

So any suggestions as to what kind of KV range I should be looking for and I was planning on sensored

Cheers
Stu