My friends Impala SS

[Aztlanahauc]

I have a friend who has a problem with his Impala. When the revs get to the 4K rpms the motor starts to knock. Seems like the noise is coming from the valve covers. I think he wiped out the motor (has over 100k on it) but I want to make sure it is not the opti spark. What should I look for.

Thanks.

[revolutionary]

drain the oil and look for shiny copper or silver dust or flakes. hopefully he has a magnetic drain plug to make it easier to spot. Also cut open the oil filter carefully and pull it apart to look for bearing material. It is also posible he has a cam/lifter issue. I have seen the cam lobes wear down on some stock engines from not keeping good oil changing regimen

[Aztlanahauc]

He changed the oil and found silver specks in it. He mentioned that this started to happen after he had a little stoplight drag race with a Camaro.

Well I guess it will be new motor time for him..