I have an 83 Z28 with a new build mid 70's block 350. I've tried everything I know other than new radiator and still getting too hot for my taste. Because I know you'll ask...heres what I have and have done. 350 mild cam 882 heads w/2.02/1.65 valves ported and polished, performer intake, shorty headers, hyp pistons, Holley 650, non cc HEI Dist. I know these cars run warm stock from the factory, but I wouldnt think non cc 350 should run this warm. In a 15 mile run it is pushing 210 constantly and when I stop or slow it starts raising. I havent let it get past 220 before shutting it down, so dont know how high it would go. Engine only has about 300 miles and dont want to get it too hot especially during break in. Heres what I've checked and tried..Changed thermostat and put in 160 degree. Flushed entire system till ran clear, Air Dam is there and in good shape, water in radiator seems to be circulating well when cap is off. I live in the country and this 15 mile drive is mostly free from stops and starts and can run as fast or slow as I like, I was running steady 60 mph. My concern is if its doing this in 70 degree weather on highway...whats it gonna do in town start and stop in 90 degree this summer. Could heater core be the problem? No leaking but when I turn heat switch from cold to hot it hardly blows out vents but when its in cold position it blows hard, not sure what would cause this or if it has anything to do w/my operating temp of motor. Sorry this is so long but want to be thorough with everything. Someone please help.

 

I cant help you but im having the same sort of problem with my heater when its on hot it hardly blows any but on cold it blows way harder.

 

i had the same problem & i realized that in the 80's before these plastic fans came out, old skool fans stayed on all the time & had no overheating problems on muscle cars, so i wired mine to come on whenever i turn the key to start, & it has improved the overheating issue. u can invest in a high flow water pump & a 4 core radiator & that will help also.

 

Well guess I forgot to mention I'm runnin old school.....ie fan connected to pulley, on all the time. After reading hundreds of posts I did find something interesting on the sending unit location. Mine is in the head and several posts made sense that this location is by far hotter than next to thermostat on intake. I might switch and see if that helps with operating temp. But still dont know about fan blowing hard on cold, and hardly feeling anything on hot. Any ideas?

 

I would try an aftermarket gauge to verify the temp. With the electric fans, they don't come on till 235 degrees.

 

maybe a 3 or 4 core alum. rad. by be cool would work. try that out.. I myself went through 2 be cools but then i found a guy in arizona that makes custom rads. what he did was took out the oil line and made it run somewhere else in the rad. and now my car wont get past 160

 

I am not sure the setup on early camaros, but make sure the plastic airdam on bottom is actually making air go up instead of down and make sure the plastics inside nose/front bumper are not interfering with the cooling.