I have a  1988 Targa.  I need to know how to bring down the coolant temperature in high heat states. I live in Florida.  I have had the car for about 3 years and the temp gauge reaches 235 and sometimes up to 240 in the summer while standing still in traffic.  I assume I have the stock radiator and stock single fan. I approximate size of 12 to 14 inches in diameter.  Has anyone solved this problem with a larger capacity raditor and either a larger fan.  I have seen some 'vettes with duel fans. Any help or ideas would be greatly appreciated. Please mention the names and phone numbers of companies with the appropriate problem solvers and parts.  Thank you.  P.S. I realized that the exchangement of parts may cause problems with the computer.  I am looking for the perfect fix.  If you have had this problem and repaired the problem PLEASE let me know the solution.  I would love to drive my 'vette in the summer without having to keep one eye on the temperature guage.      

|UPDATED|1/5/2019 4:45:18 PM (AZT)|/UPDATED|

What you're experiencing with the cooling system temperature is not usual and is normal given the environmental circumstances you've stated.  However, most C4 owners experience a maximum of 230 to 235 degrees.  240 degrees is getting a little too high.  When was the last time the cooling system was serviced and how many miles ago was it?  Have you checked for debris stuck on the front of the radiator?  Also, I recommend knowing the details and not assuming anything.