For V7 sti needs to be a uprated strong clutch,

 

What torque level?

 

I think its more the torque on the clutch and not the bhp thats a factor, I think you have the 240mm clutch the same as mine currently, I removed a high performance clutch when my gearbox was done, and fitted an original, this was on the advice of the subaru rally guys who are based not to far from me, but I am only running around 310bhp, I told them what I was planning a tad under 400bhp they did not see a problem, but just an opinion, I will find out when the power is up.