ok so i picked up my new addition to the family a couple weeks ago and have been tinkering with it replaced the factory single fan(motor was burnt). it didnt have a/c so i went through the system a couple days ago air blows nice and cold. (i live in las vegas btw stop and go on the freeway). my brother gets home and tells me it heated up to about 240* so he shut the a/c off it cools down a little. so i goto the junk yard today and pick up a set of 4th gen fans modded the shrowd to fit around the steering gear and modified the upper hold rad. hold down fit like a dream got her wired up on a new factory relay with the ground switch on both fans so i can turn on at will. let it sit in the sun for about 30 min, got to 200 i was like cool i fixed it guess again temp went to 240 within a mile.
also all the factory ducktin and airdamn is in tact and good condition

my question is what do i do to get this thing to cool better?

mods;
-new hoses
-reverse flush rad and block
-cleaned condensor and radiator(no bent fins no blockage)
-moroso blue ring in place of thermostat
-toggel to green/wht. wire on relay
-4th gen dual fans(fit perfectly no gap between shroud and radiator)
and relay wired properly(brown and green/wht, piggy backed to factory relay, power to junction block next to battery with #14 fuseable link)

what i will be doing tomorrow
-block test
-radiator cap

sorry for the mispelling.

1992 rs 305 tbi t-5

 

moroso blue ring? is this like a restrictor instead of a thermostat. if the fans are on the stock settings then they dont come on till 220. a 180 thermostat and a new temp switch to turn the fans on sooner would help.

 

yes its a restrictor ring that i have ran in sevral diffrent motors and worked fine. i have the fans wired so i can turn them on at will so yes i have the fans running all the time(its 115 here) i did a block test and replaced the radiator cap with a new gm unit and it still is heating up.

 

I have the exact same problem with mine. I have a 91 Camaro and the cooling system stays at 195 degrees consistently unless i turn on the AC. Within 20 miles, the car will start to overheat if the AC is on, once you turn it off, the temp goes back to normal. If left on, it will take the temp all the way to the red on the gauge.

I've replaced the following equipment on the car within the last month:
Radiator
Water Pump
All Hoses
Heater Core
Heater Core Bypass
195 Degree Thermostat
Serpentine Belt
No fluid leaks

I don't think that the compressor is bad b/c it doesn't lock up like it would if the high side pressure was going too high. In addition to that, I know that the electric fan is most likely moving enough air to cool the R12 down b/c the compressor operates the way it should without cutting on and off every 2-3 seconds as it would if the high side pressure was too high.

As of now, the system doesn't have any R12 leaks and blows very cold while running the AC.

One idea that i'm going to try is replacing the belt tensioner. The only other thing that i can think of is that it may be allowing belt slippage when the compressor turns on.

Any other ideas?