have owned my ctd for about 9 mos. and 20k miles now. noticed the smokescrew cap was missing and the fuel screw collar was missing when i bought the truck. however there was,and still is paint seal marks, red paint on some of the pump screws. so i assumed the pump may have been modded(hence the modded pump line in my sig. sooooooooo curiosity got the best of me sunday and i took the top off the diaphram housing. the smoke screw was not even contacting the diaphram and the fuel cone was turned to the leanest position. sooooooo i turned the cone to full rich and dialed in 3 turns on the smoke screw. woooooow runs like a whole diff. truck. wentfrom 12 to 17psi with these mods and i still have more tuning to do. GREAT WEBSITE U GUYS HAVE HERE AND THANKS... ... ...