Since there is no noise from the bottom end of the engine I also agree about just putting on two new heads and going on down the road. These engines are very strong.

On the catalytic converter as Alloro stated you will find that you need to change it out. Now with your van being a 98 you can try and see if it will behave. The PCM will do its own testing of the converter and when there is a problem it will turn on the MIL (Malfunction Indicator Lamp or commonly known as the "Check Engine" light) and most likely show a P0420 code saying the the "Catalytic efficiency below threshold" at that time you will need to change the cat out.

 

If MIL = Check Engine Lamp, then does CEL = Maintenance Indicator Lamp?

 

see i am thinking that you are right. i did some hunting around and found that the lower end is structured a lot better than the heads. the heads seem to be the weak link on this but i still wasnt sure if this was a good idea or a lost cause that i wanted to believe could work. sounds like it could very well work, no guarantee obviously, but it sounds like i would be dumb to just leave it to die.


smart ***