If it won't stay cool at highway speeds its not the fans. You have a flow problem somewhere, either the radiator is plugged, or the pump is going out or is inadequate. Maybe the lower hose is collapsing under load? Bottom line is, it's not likely to be the fans that are your problem, they shouldn't even run at highways speeds. And if they are running at highway speeds that could point to another problem, like the fan switch/controller. Which also begs the question, what is your controller set at to run the fans? Because if the controller is set to keep the engine at 200* (which isn't that hot, BTW) it will run 200* all the time, and it will run the same on a cool day and a hot day.
I use a 1995- 2000 V6 ford contour, two speed, dual electric fan set up on a 26" Champion 3 core radiator. This is in my Duster, but it doesn't matter much. The 340 that fan set up is cooling is .060" over and is putting out 400+ hp. The fans NEVER run if I'm moving faster than 15mph or so, and that's true on 110* F days. Make sure you're also running a good fan controller, the electric fans can only be as good as their controller. I run a Dakota Digital 2750 controller. Works awesome, lets you program the on and off temperatures for both the low and high speeds on the fans, plus allows for things like running the fans after the car is shut down to prevent heat soak when you shut down. I also run a high volume water pump. Whole thing almost works too well, at freeway speeds in the winter I stay at whatever temperature the thermostat is, currently a 180*. In the summer the fans still cycle on and off, they never run continuously. I've never even had the fans kick up to high speed, so, based on my fan controller settings that means the engine has never been over 205*. And I've driven the car more than a few times in 110* F weather, it's my daily driver and it gets hot around Sacramento in the summer. Heck I didn't even open up the radiator support, it's for a 22" radiator.
I just love reading about how everyone spends money for a electric fan, aluminum rad, headers. etc.
Both of our rides have the stock fan clutch, shroud, no headers. upgrade rad to 3 core.
Both run at 195 'f.
After purchasing GCpe.
Had to replace water pump on GC cheap china aluminum replaced it with cast iron.
replaced fan clutch, fan belts and flush rad......new coolant.
Hey the 318 in my Challenger runs at 195* all day long too, it just has a plain mechanical fan, not even a fan clutch. Stock 2 core radiator, stock water pump. It's because it's basically a stock engine and doesn't make much in the way of horsepower, with a 4 barrel and headers maybe 250 tops. More horsepower = more cooling needed. Pretty simple. If you've got a stock engine, the stock cooling system should be more than adequate. 400+ hp .060" 340 small block, you'd better improve the cooling. Horsepower is heat.
Personally,
I love reading about guys with stock spec engines. Means my car is faster, and a hell of a lot more fun.
***Edit***
year range for Contour electric fans corrected, added V6 model info.
