Toyota Repair: top end knock Celica GT 96, celica gt, engine cold

Question
I have a top end knock that initially came in at 3000 rpm and seemed to go at about 3500. When the engine is cold there is no noise at all once warm and this time can vary from 5 - 20 mins the knock is louder and comes in at anything over tickover. The knock is a heavier metallic sound and the noise seems to vary on different days. The engine was meant to be reconditioned 12000 miles ago but I am Not sure of this if it is not it has done 133000. One more thing the engine when running ok seems to be a lot quicker than a standard celica. Sorry I dot know what has been  done. Basisically at 6000 it feels like a turbo is kicking in thanks for your time paul

Answer
You may want to consider checking the valve adjustment, these are adjustable using different thickness shims but it's easy to just check the clearances and then deal with the one that may be the problem. Check with the engine cold. Another possible cause that comes to mind is that one of the pistons wristpin has to much clearance, the reason there is no noise at cold is due to expansion rates of the different metals when the tempeture changes, I don't think it's a piston noise such as if the piston was worn because then the noise would be loudest when the engine is cold but it could be a piston wristpin fitted too loose in the piston.