Slowly progressing, I've come back to this project. I recently won an ebay auction for the chevy blazer 4.6L EGR valve shown below. I'm hoping to develop some sort of control for it. If anyone has any insight as to how these work I'm all ears. I'm hoping I can actuate it gradually instead of just on/off, but it looks like its more of an on/off deal.
I picked this valve because of the engine size. According to the chart a few posts ago, 10% EGR flow really knocks down on NOx. I am assuming that this valve will flow about 10% of a 4.6L engine's intake at cruise. An incredibly rough estimate shows that that will be ~30% flow on a 1.5L engine. We'll see if that is too much once coupled with the TDI EGR cooler.
