Hi I have a 383 with all the info in my sig. With the AC off the car runs around 180 to 190 even when the outside temp is in the 90's. But when I turn the AC on the temp starts to climb. When driving the temp climbs to around 230 but when at a stop light it doesn't stop climbing the temp will go up to 260 if I let it. I still have the stock cooling system with a 160 thermostat. Do I need to start looking into a aftermarket system?
Thanks

 

Did you bleed the cooling system through both bleeder screws? Might have air lock going back to your heater box?

 

Are the fans coming on? They should come on when the AC is on.

 

Yes the system was completely bleed and both fans are coming on. I think that it's in the tune so Monday I'm calling the guy that tuned the car.
Thanks

 

I'm not sure if the tune is the problem. I'd lean towards something with the cooling system or condenser. If the fans are coming on...I don't see how the tune could be causing the issue.

 

I had a strange intermittent overheating issue with mine (auto).
It didn't necessarily overheat, but the temps would get higher
than normal, every now and then.

Just recently, I ordered a new radiator (for piece of mind - car has
160+ miles). Well, when I pulled the radiator back and down through
the bottom, there was a fast-food hamburger bag covering about
an upper (passenger side) 1/4 of the radiator. How the heck it found
its way up and in-between the radiator and condenser is beyond me.
(considering the gap between the two).

There's NO doubt the issue was with the bag wedged between the
radiator and condenser - however, I'm also sure changing out the
radiator helped considerably.

The point is, check for things that may not be obvious (and simple).

 

Thanks for the ideas. I've looked over the cooling system a couple of times. The cooling system works fine when the AC is off and stays around 180-190 with a air temp in the 90's. Thats why I'm thinking the tune. I think when he tuned the car he adjusted the timing of the engine to give me max power with the AC on and he might have adjusted to much. So when the AC is on the timing is adjusted so much that now the cooling system can't keep up. Keep giving he things to look at and I'll do that until Monday when I call my tuner.
Thanks

 

The AC turns off when you go WOT. Why would he tune it for max power with the AC on?

The extra heat coming off the condensor when the AC is on is overloading the radiator.

 

Dumb question, Fred ... so why not put the radiator ahead of the condensor?

 

He did the tuning with the AC off. I was just thinking that he was trying to get the most out of the car and adjusted the timing to much when the AC is on. The reason that I'm thinking tune and not the cooling system is because everything is working fine with the AC off. But yes the condensor is heating up with the AC on and radiator can't keep up. Could I need a bigger radiator?
Thanks for the help

 

I suspect the condensor needs the colder air to work. It wouldn't work very well if you were trying to condense the R134a with 200* air coming off the back of the radiator.

 

I haven't gotten a hold of the tuner yet. Do you guys think it's a problem with the tune or cooling system? Also if the R134 was low would that affect the cooling?
Thanks

 

I have the same problem. My temp guage starts climbing asoon as i turn on the AC. If it is heat from the condensor, what can be done to fix the problem? Thanks

 

I've got the same problem on a 95 LT1 stroked to 383, procharged 9psi, methanol injection. I built the car with A/C so I can cruise when its hot outside and its really irratating when I can't figure this out. Seems Nobody has an awnser for this one??????????????????

 

Same problem here.