ok so the garage rebuilt my engine on my v3 which i still havent had for more than an hour!!, started fine for 30 seconds than a very loud tapping from one of the heads started, they think its a shim??? how would this happen?? can anyone explain this to me more clearly or are they just fobbing me off. they recon its only an hour to put right??
getting a bit annoyed with them now as i picked it up over a week ago and it seized within an hour, they rebuild it and it lasted 30 seconds and im now not even sure if they have used standard forged pistons or wrx cast ones, just feeling really let down now

 

Unusual for a STi under bucket shim to become displaced and rattle due to the design of them.
It might be a broken cam cap bolt causing the rattle or even a blocked oil gallery on the head causing oil starvation - this normally only happens when the heads/oil gallerys/oil restrictor are not cleaned properly after an engine failure.
Hope you get it sorted mate.

 

so basically they have just chucked a short motor in it and not even stripped down my heads to see if there was a problem in there which caused the engine to seize in the first place!!!
they told me the oil pump failed first time around???

 

Its unusual for a pump to actually fail - when big end failure occurs due to lack of oil/pressure/detonation damage/cooling problems etc etc,the debris from the bearing material quickly gets around the oil gallerys and through the oil pump resulting in the debris jamming the oil pressure relief valve open and the oil pressure drops to virtually nothing.
If you are doing 4000rpm (for example) at the time the oil pressure relief valve sticks in the relief position - it takes seconds to destroy the bottom end of the engine.
A lot of debris will also get caught in the Modine oil cooler,so if this is not cleaned/replaced at the time of the build - it will fail again.
Its hard to say why an engine has failed without looking at it and examining the pump,crank,bearings etc to form an opinion.
You have obviously spent good money having it repaired,so if you dont get what you pay for from the repairers,then get in touch with trading standards.

Mick