alright, i tok it to a mechanic, he said that its defitly not the bottom end!!

he said the noise would be consistant through all the revs if it was the bottom, and it would not idle steadily, which it does.

the noise was coming from underneth the rocker cover, so they are going to take it apart, and just tell me whats wrong. the think it is the tappets, but they will investigate tomroow morning at 8am! they say in one hour £60, they will tell me my problem. if its in the top end of the engine, which sounds like just one side, its only a limited amount of options it could be... so i will keep all posted!!

thanks for the help so far!!