Are standard sierra discs and calipers with upgraded pads up to the job on a care with a zetec running 150bhp??

They don't need upgraded pads, they stop a ton and half of Sierra when they are fitted to that and your car will weigh a lot less hopefully. If the pads are harder they will not warm up quick enough.

YES

Yes and on standard pads too.

Cheers

Rich

Suggest changing to solid discs to get the best out of them, but depends on what your doing with it.