ok does it over heat on other roads or just the freeway

do you have an after-market grill? if so is it allowing enough air through to the radiator? some of the grills with really small holes in them restrict the airflow too much, causing even a car with all brand new stuff to over heat

check to see if your air damn under the front of your camaro is torn or is gone.. That air damn pushes air to your radiator.. same situation happened to me and I purchased one since the stock air damn wasn't there and it cured my problems..

As I said in your other post it's likely air in the system.  
Fairly likely considering you have new components.

Also the air damn may be the problem, but usually that only happens on a car where the radiator is dirty and not letting air flow through as freely, since you've got a new radiator I wouldn't think that this would be the problem though I could be wrong.

simple answer here.  Have you changed the thermostat?  it may be stuck open so on the freeway the water is constantly moving, causing it to slowly heat up until all of your coolant is so hot it cant cool the engine, causing the temp to go up...
message me if you have any question, have been a camaro tech for 6 years.

Another thing that I have run into on numerous chevy's aswell is fan shroud.  You have to have a fan shroud on there or it will over heat.   My experience with this is on my 1972 Chevy c20 Custom Camper pick up with the Stock 402 Big Block.  Fan shroud broke and I was running it for a little bit with out it and it started over heating a little on the freeway.  Also could be thermostat.


I would check thermostat, fan shroud, and air damn.  Three key elements.  Also what is your coolant to water ratio, should be about 50 50 depending on weather conditions.

just a simple solution---when was the last time the radiator cap was changed? I had a 87 pontiac gta, it did the same thing and it was just a radiator cap. Also check the air dam mounted in the nose of the car, it deflects air from the ground into the radiator. should be a three piece unit on your model. Although i had an 82 trans am with a 396 big block i installed and it did not overheat, and I had removed the air dam. As a rule of thumb look at simple maintainence first (I.E.-Flush cooling system, change anti freeze, etc)

Just a question but how does it over heat if the thermostat is stuck open? Wouldnt that mean it would running 2 cool cause its flowwing coolant all the time.

88 dont have a shroud it has electrick fan,replace rad cap,theromostat and yout temp collent senser,if your engine is tuned port the tcs is in front left ot tp looking at engine,if no tp is located around thermostat housing,is scrud into intake.also check your oil if milkey looking,you have a blown head gasket.also they can blow on exhoust side crank it let it run a few minutes and see if your exhoust smels of antifreze.