Re: Is anyone using the dual 15\" electric truck fans from Flex-a-lite?
A 4 core radiator causes problems of its own...you've got more surface area yes, but theoretically you slow down airflow. On top of that, the wider cores on the AL radiators are more efficient. Less airflow problems, plus more surface area.
I've got a 415 in my car that just will not stay cool at idle. Well, it will, but it isn't as low as I think it should be. I'm limited by radiator size though, it's probably 2" shorter and a few inches narrower than the truck ones. An AL radiator may be in the works for it, but thats my project AFTER truck is done. /forums/images/graemlins/smile.gif
At idle, short of increasing airflow through the radiator, since it's a closed system, more coolant capacity WILL help...as long as your fan is up to the task of bringing the temp down enough.
Drop your coolant mixture down to the lowest possible. I'm going to go with 33%, since I do see temperatures down into the single digits or slightly below, and thats about as far as 33% will get you. 25% antifreeze seems to be the bare minimum for it to do its job (one of which is to protect against cooling system corrosion) based on the antifreeze charts (on the bottles) so I wouldn't go any lower than that.
Don't pay attention to the "boil over protection" claims on the bottles. Pressure is a FAR greater infuence on boiling temp than antifreeze is. If you check into all those claims, their boilover rating is at 15lbs of pressure. You gain VERY little in boilover protection because of antifreeze. (3* for every 1 pound of pressure without antifreeze...I would never want my engine to get near 257*, the theoretical boiling point in a system with a 15PSI cap and straight water, regardless if the coolant boiled or not..)
Water is the best COOLANT you can use, so if you can drop the antifreeze ratio down, you will at least make it easier for your cooling system, even if you don't eliminate the problem.
