cooling system

its not the 200 its getting to 210 and I shut it down, only at idel, if I run it at all the temp comes right down. What is to hot?? I am sure it is an air flow problemis ithurting that I dont have a hood right now and the fan can draw air from all around the radiator?? I have a 1 3/4 space on the flex fan now and I cant get the fan any closer. I am also supposed to run a 22LBS cap on the radiator but can only find a 20 could this have something to do with it?