ok so the radiatior is filled and im running the car....and when i open the coolent valves to get the air out...some comes out...and it bubbles...then nothing...the 30secounds more comes out in like bubbles and then theres nothing...so do i have to keep the car running till a steady stream comes out??

its a 3100 v6 in a 1995 monte carlo ls..i just replaced the headgaskets and upper and lower manifold gaskets along with the thermostat

 

I would get as much air as possible out, then just start driving it...

As you drive it, the remaining air should naturally work its way out, especially as the car heats up to operating temp. and then cools back down. The car will eventually get rid of all the air in the system, and will replace it with coolant from you over flow container. So make sure to keep a close eye on your coolant overflow, and keep it full.

 

Try the valve on the thermostat, take a small screwdriver and unscrew it a little bit with a rag around it. do that until coolant starts to come out.