yeah too rite, dependin on the noise it could even have been a loose or damaged mount sumthin not fitted right or anything really, if it were the engines internals then it wont be a 'good' noise, big ends, mains maybe or maybe the pistons were slappin from block bein bored but pistons not bein quite right size
to run in a lump lots of ppl say different things, i'd be happy with sensible driving for a 1000 miles and then start to increase the leathering i'd give it, u wanna run it at different revs over time, tho, so some long driving and some higher revs drivin too, seems to be the best way to run a lump in, mind u ive also know ppl to thrash a car from brand new (not turbo cars tho) and they are quicker cars, the lumps wont last as long tho, weird innit