Oct 16, 2016
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I have a 96 LT1 and because of overheating issues (during summertime stop & go traffic) I am thinking of replacing my radiator.
Note my 96 only has 20k original kilometres (sat for extended period as original owners only drove about 500 kilometres a year), I’ve already had the rad flushed and antifreeze replaced.
Has anyone replaced their radiator and if so did you replace with stock or with an aluminum 2 or 3 core radiator?
Did replacing the radiator solve overheating issues?
Thanks
Derek
 
I replaced mine with stock equivalent. All overheating was solved. Mine used to go up to about 265f even with flush and new thermostat and waterpump. Now runs around 190 - 200f. I have heard that aluminum is lighter , but tends to be less efficient than steel/copper.
 
I replaced mine with stock equivalent. All overheating was solved. Mine used to go up to about 265f even with flush and new thermostat and waterpump. Now runs around 190 - 200f. I have heard that aluminum is lighter , but tends to be less efficient than steel/copper.

Thanks Vintageracer what make of rad did you get for the replacement?
 
What is the "normal" operating temperature for the average C4? My 86 crept up to 217 in traffic, and then touched 230 in my driveway. The day was hot, around 90. Got this car a short while ago, but rad cap seems good, maybe recent, antifreeze is clean, bright green, hoses look fine. Scares the hell out of me, don't wanna blow up a good engine. Car has only 50000 miles on it (82000 klms) Should have a 195 degree thermostat in it, (factory) but the fan seems to kick in only when it's really hot.
 
What is the "normal" operating temperature for the average C4? My 86 crept up to 217 in traffic, and then touched 230 in my driveway. The day was hot, around 90. Got this car a short while ago, but rad cap seems good, maybe recent, antifreeze is clean, bright green, hoses look fine. Scares the hell out of me, don't wanna blow up a good engine. Car has only 50000 miles on it (82000 klms) Should have a 195 degree thermostat in it, (factory) but the fan seems to kick in only when it's really hot.

Your experiences are similar to mine. I get about 210 in traffic on hot days and high 220s after pulling into the garage at shutdown. Driving in Summer runs around 185 - 200 normally.
Before my new rad it would soar to about 260:Arghh:!!! (fortunately, no apparent damage)
 
Been reading about how important it is to keep the rad free of debris, seems the design of the air inlet, low to the ground, causes a lot of stuff to get sucked up. Carefully ran the garden hose through the rad from the inside to wash off debris, so I'll see if that helped.
 
These are normal temperature for those C4’s
Fans starts at 224 and 228, if you want to run cooler, have the PCM tuned to start the fans earlier
 
I have a 1984 and normal temps for me are around 185 on the highway and running 200 in town in traffic..
I have searched a lot and they can apparently run 210-230 no problem
 
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Although antifreeze looked recent and tested well, I drained it out, flushed the rad, and refilled with new, including emptying and refilling overflow tank. I also added a bottle of Royal Purple cooling additive, and that really made a difference. Stays down around 205 when moving, nothing higher that 225 in stop and go traffic, immediately dropping down 10 degrees as soon as I start moving. Can't complain about that!
 
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My 92 had the exact same heat issues. Swapped the radiator, problem solved. Also got a new thermostat before the radiator. Once the old radiator was out, it was easy to see all the small stones, hair, other debris that was jammed into the fins. The new rad was quite cheap. Kind of a pain in the ass to change. But wasn’t that bad. The car had approximately 90000kms on it at that time.
 
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