Originally Posted by stroker_SS
My 84 camaro, 355 iron heads, stock style radiator, chrome half circle fan shroud, aluminum flex fan, stock waterpump and pulleys,thermostat or no thermostat it has an overheating problem, only on the freeways at speeds of 70+ mph or when sitting and idling. At freeway speeds (no od btw) it slowly overheats, but once it gets to 210*+ it starts creeping up in temp and doesn't come down, unless you shut it down and let it cool off.
i have no idea how old the waterpump is, but it doesn't leak, and the car doesn't overheat as long as your not sitting still or running it hard.
i've had a couple of ideas on how to get the temp down and stay down one of them being making a sheet metal fan shroud and a single 15 or 16" electric puller fan.
what would cool better a shroud that covers the entire back of the radiator with the fan in the center or, just mounting the fan on the radiator no shroud.
I really want to be able to bury the throttle on this thing or be bumper to bumper in cruise night traffic and have no overheating problems. I flushed the radiator and put in new 50/50 mix antrifreeze and that helped some but not enough for me so what should i try first?
Typically an engine that keeps getting hotter while at cruise or above is having coolant circulation problems, usually through the radiator core. Chemical flushes and back flushing is usually an inadequate treatment by the time this cooling problem is noticeable. The solution is two possibilities, 1) if the radiator is copper/brass it can be "rodded" by a radiator shop; this is passing a rod of suitable size through the core tubes to scrape out deposits. 2) Would be replacement of the radiator.
The half shroud is useless and is contributing to your idle cooling issue. The factory shroud is needed to pull air through the entire core by the factory fan. A situation less than what the factory put there is not capable of moving sufficient air thru the radiator unless you convert to electric fans with adequate shrouding to insure air is pulled across the entire core.