I've got a -94 Conv LT1. At highway the temp is around 90-95 C (194-203 F). When at idle, or in town, it can go up to over 110 C (230 F). The primary fan kicks in at 108 C (~226 F). Is that normal? At what temp should secondary fan start?

Completely normal. I have an 88, and the fans on mine kick in at the same temp as you. 108 C. As for the secondary, I'm not sure; mine has never came on, but from what I read this too is normal. Seems very hot to me as well, but this is the way these cars were designed.

Yes, so I've heard... My problem is that only one of the cooling fans is working, the left one, and that the temp gets high. Also the AC is not working. I went to a local US car workshop today. He made a quick test and said the AC needed refilling. He also said the reson the right hand fan (behind the AC condenser) doesn't work might be that the AC gas level is to low. Can that be correct..? On wednesday I'll refill the AC then we'll see...

Very normal. If the A/C is running, the engine temperature runs cooler b/c the fan/fans run constantly.

Have the mechanic check for leaks as well. There could a leaky seal somewhere.

What you describe is normal.  The secondary fan comes on at 235 deg F, and is not locked out by low AC refrigerant pressure. 

Corveddie

Problem solved! I had the AC filled up yesterday and engine temp is now OK, around 92C/200F when driving and 95C/203F when idle. Left fan is now working when the ac is on. Now I sleep like a baby... :-)

I'm driving a 1990 in south Florida and was concerned that only one fan was on most of the time. The second fan is controlled by a pressure switch on the freon line to the A/C coil. I simply unplugged the connector to the pressure switch and both fans run whenever the engine is running.

Has anyone put a 180 degree thermostat in ? I did this on my 454 Vortec Dually. Changed O2 sensors. Temp W/ AC in South Florida in summer never goes above 200 F.   Also, would the 180 thermo preclude the second fan from operating? Corvette america hasa a switch where you can program what temp. for second fan.