HELP! 91 Camero RS overheating issues!!

I have a 91 Chevy Camero RS 305 V8 TBI. It sat for about 4 months before I bought it. So far I have put in a new battery, top/bottom rad. hoses, new 195 thermostate, a heavy duty water pump (ultimate coolant) , new splug, wires, cap/rodor, PCV valve, air filter. And it is STILL RUNNING LIKE S%&T!!! The fan always kicks on at 220 ( which is almost immediatly after I start the car.) But the fan also won't stay on unless I have the key on.I would like to change the temp. that the fan will come on at to more like 180, if that is possible. But I am not sure as to how to do all this! It just runs really sluggish. Last night I had the " medal to the metal " and it barly wanted to move. It has no " get up and go!" Some times when I'm at idle l, it wants to stall out too. Not to mention, I have been getting really crappy gas milage!! I am at a loss here! Somebody PLEASE HELP!!! If some one has any advice, please email or call at 702-369-0791 or 702- 878-2245 :confused:

Morley suggested a while ago to check out,
http://www.hypertech.com/fanswitch.html,
for a temp switch that will come on at a lower temp

Bad idle and crappy milage could be related to the EGR, but that's a guess.

Put a lower temp thermostat such as a 160 in it. For the fan, you can get a lower temp fan switch. Its in the side of the block from under the car with a wire attached to it.