Ok my car was overhating I changed the warterpump and hoes adde a 160 degree thermostat and it's over heating faster then it use to befor the the new water pump instal at first I thought it was the coolant temperature sensor but could the thermostat not be opening up?

 

Do the fans come one either on their own or with the ac on?

Did you pull the rad. support plate off to see if anything got in front of the radiator?

Have you topped it off while you visually saw flow inside the cap and shut it off and checked the level the next morning?

 

You may have air in the lines. I would rebleed the coolant to make sure all of the air is out.

 

Did you get the correct thermostat for the LT1?

Courtesy of Shoebox:

http://shbox.com/1/tstat.jpg

The thermostat doesn't control the overheating. The temp is controlled by the fans, as operated by the PCM.

What temperature is the dash gauge indicating when you feel it is "overheating"?

Do you have access to a scanner to allow you to observe the coolant temperature being sent to the PCM from the temp sensor in the water pump housing?