I have been reading your thread on your KR issues and asked questions that were not answered. There are many things that can cause knock. The previous owner hot rodding the car isnt one of them. If he doamaged the motor, you would have known by now. You need to get your tune down, find out what the fuel system is, make sure you have no vacuum leaks, clean the injectors, etc. Please take time to learn these cars before getting frustrated. They arent that complicated, just take time to learn.