when i shut my turbo 98 prelude off....i hear this clank noise...it happens like 1-5min after i shut the car off....i think it is coming from the mani...or the hot side of the turbo...it will happen 4 to 5 times(couple min after each other)
almost like metal cooling down after expanding...

i was wondering if anybody else has this problem and if it is normal

 

"almost like metal cooling down after expanding..."

I think you hit the nail on the head.