Hey guys I just wanted to confirm that it does seem like all contours with a build date after 5/99 have a returnless fuel system. I just got the manifold and injectors installed and despite my Pro Flow being calibrated for the 17lb's the car still runs good without throwing off any CEL's. My mystique was built in 8/99 so it did infact have the returnless system much to my surprise. Now that I have the extra fuel and the enlarged lower to match the rest of the Svt upgrades I should finally be ready to dyno tune the car to adjust the A/F mixture with my chip in a few weeks. Can't wait to post the numbers, I have high expectations!