72 bluNblu
Which Dakota model fan controller did you use?
It's a Dakota Digital PAC 2750.
Dakota Digital Programmable Dual Fan Controllers PAC-2750
That is accurate, but so is what I have been saying, there will always be conditions that stress your system, but your cooling system needs to be able to cool your system in all environments that you travel in down to your thermostats range, or you risk the possibility that you will overheat. If you live in the dessert you probably need more radiator and air flow than if you live in Alaska. If you have the proper thermostat and your car doesn't cool down to it when you are on the highway then at some point you may be low on antifreeze and boil over or you may boil over just idleing. My point is you need more cooling capability than you use and let the thermostat regulate what you need. Yes as I have said many times the thermostat only sets the lower temperature, but your system should be able to hold it there in all situations, even idling, or the next time you are little low on antifreeze you will overheat.
You completely misunderstand what a thermostat is for. It's
only purpose is to set the minimum temperature.
And no, a properly functioning cooling system does not need to be able to cool the system until the thermostat closes under all conditions. It has to
maintain temperature. That's the goal. To maintain the operating temperature within the operating range. Of which the thermostat controls only the lower limit. That's it.
There are a lot of variables at work, and they're always changing. The GPM of the water pump changes with engine RPM. So does the CFM of the fan if you're using a mechanical fan. And if you have an electric fan you may have multiple speeds and be able to control all the temperatures they come on at. The rate at which the coolant absorbs energy changes with its temperature and pressure. And the rate at which the radiator can shed energy changes with the outside temperature. All of that means that your cooling system, even a perfectly capable one, will not maintain the same temperature under all conditions. The temperature it will be able to maintain changes with the conditions. And that's fine, as long as it can maintain a temperature within the operating range. When it's 110*F out and you're stuck in traffic, your cooling system does not have to be a able to lower the coolant temperature until the thermostat closes. It just has to be able to maintain a temperature in the range. If that's 200*F, you're fine. You're only in trouble if your cooling system can't keep the coolant from
gaining temperature. If it can hold 200*F stuck in traffic and cools to 190* when you start moving, everything's great.
In this case the OP's car is holding 196* on the highway, which is probably still a little too high given that it's not the middle of summer yet. But he reduced his operating temperature significantly by correcting his timing, and more tuning may be needed here. His radiator capacity shouldn't be an issue, there are other members here running 26" aluminum 3 core radiators with no issues at all. Myself included. We already know his fans aren't up to task by the way the car heats up when it's not moving.
Maybe he got a lemon of a radiator, quality control is a little lacking on the cheaper radiators. But my bet is still on tuning and fan capacity.
