I keep reading that adding an e-fan will improve MPGs.

If we are talking about an electric radiator fan over mechanical, please explain how that increases MPGs?

In which case, why wouldn't I just go to a 180* tStat? Wait I know...cause the warmer block temp equals better MPGs.

 

hundreds of posts over this, It is simple, You are reducing the parasitic draw on the engine from the fluid clutch fan. It really has nothing to do with cooling. And it does work, I gained 1mpg by replacing the clutch fan with the e-fan. And there was definitely a seat of the pants increase.

 

I see, the pull of the fan is the issue...mmmm

 

Yes, from what I've read it will give you one or two mpg increase as well as a hp gain since the motor isn't having to work to move that huge fan.

 

Just think of it as you working outside with a back pack that weighs 10lbs versus doing the same work without it.

 

What about a smaller fan with no clutch, coupled with a 180* stat?

Ofcourse I'd need to find a fan that's smaller with the correct bolt pattern.

They should do that stock, especailly if it's a MPG helper...

 

Smaller fan = lower CFM. No Good...

 

Also 180* thermostat and E-fan are really pretty much unrelated. E-fan is about reducing drag on the engine and the T-stat is about running the engine at a cooler range. Personally I never liked the idea of the 180* T-stat, however to each there own.

 

A 180* T-stat has it's place, but I agree that it's not the right move for everyone. Heavy towers/haulers will benefit from the "head start" of the stat opening at a lower temp to keep cool.

It's also a slight power adder, by virtue of the fact that a PCM will dump slightly more fuel at the cooler temp (which also will negatively impact fuel economy slightly).

But the big benefit of dumping more fuel is that it will richen the A/F ratio and some people may need this little bit of bump because they have mods that will lean you out. Someone who has MULTIPLE mods that do this (me for instance with LT headers, a CAI and a tuner set to Performance) find it to be a very inexpensive way to put the A/F ratio back to spec.

The only real way of knowing if you need to richen up the mix is to have your A/F ratio checked or having a device that allows you to monitor your ratio...

 

Also would be turning all the time, not just when the clutch said so.