I've got some sort of strange knocking going on in my motor, but doesn't sound like rod knock or a spun thrust washer because it doesn't seem to get faster as the car revs higher, and hasn't gotten any worse since the motor was built....

What are some other knocks associated with B-series motors...the knock is more predominant at idle, and either quits down as it accelerates, or is at least quieter than the actuall motor.....help!

Thanks,
Aj