What I mean is; warm is relative.
Some guys think 160 or 180 is warm.
I run 205 or more as warm.
Warm is good. Warmer is better. It's all good until the oil gives up, or the coolant boils
The trick is to make sure the engine temperature is stable, whatever it is; and that 7-blade fan is a key player, for as long as the clutch on it continues to work properly. And at low speed,(below about 30mph),the shroud is the third member of the three-part team.
>The properly working thermostat sets the minimum coolant temp, and has nothing to do with the maximum, unless it is defective.
>The maximum coolant temp is governed by the efficiency of the system, and varies with both engine speed and roadspeed.
>Below about 30mph, the fan/shroud/clutch/coolant circulation, are the important players.
>Circulation consists of;the rad cores, the pump, the pulley ratio, the belt,the rpm,the stat, and the hoses including the bypass.
>Idle is the hardest to deal with, as the pump-speed is the slowest, and the air has to be "sucked" thru the rad. The faster the vehicle is moving the less work the fan has to do. Which is good, cuz the faster the engine is turning, the more heat it generates. Somewhere between 30 and about 45mph, the system is loafing. Depending on the operating rpm, after about 45mph, the system is gonna start generating heat again.
>To prove your system, you can remove the stat, take it apart, and put the washer part back in. This will cause the engine to be slow to warm up. But it will allow you to judge the capability of the rest of the system.
BTW;
The fan does not suck air thru the rad.
The fan IN THE SHROUD, creates a low pressure area on the engine side of the rad. The higher air pressure on the bumper side then wants to go there. But the rad is in the way. Anything you can do to make it easier for the air to muscle it's way thru the rad, is gonna increase the efficiency of your system. But at low roadspeed, everything depends on that shroud being there. Without it, the air being slung radially around by the fan just goes round the end of the blades and back to the front side. And around and round it goes. That fan you showed is about the best design out there, so you are on the right path. You just need to duct it....... with a shroud. Then you will be well on your way to solving your cooling problem.
