i was just wondering, since rolling hills were mentioned in the original post...if the car is driving in foothills or mountains, and the air is thinner, how does that affect the normal functioning of the FEH? i'd assume higher altitude means cooler air, which means less EV...

 

If you are in a place / season with daytime highs of 50'F or less, then consider this.

Put a cardboard, or other materal in front of your radiator to block the cold airflow.
In tempertures below this, especially in stop and go, or speeds 60 MPH or less, your FEH will warm up in half the time, go into EV in half the time, stay in EV twice as long, and never overheat.

If you drive for long periods over 60 MPH, then drop the acceptible outside temp. to 45 degrees and below. ( driving fast creates more heat... )

I go into EV in 4 minutes and 1 mile at 32'F outside.

I used a cardboard block after Excel's suggestion.
I have NOT seen much of a drop in FE in the cold, Denver winter.
Ford says to expect up to 25% lower mileage in winter.
I have had 0% drop at 32'F.
I have seen about a 5% drop at 25'F.
About 10% drop at 15'F.

Of course it is cold, but dry here, so I NEVER have to use the defrost either, which helps. Putting a sheet or towel over your windshied at night will keep frost off yours if you must park outside... and maybe you can get away without using the defrost also.
-John

 

John, Do you block the lower section below the front license plate as well or just the upper section where the grill is? I have been considering doing this but haven't yet since I didn't want to risk overheating. Once I get the Scanguage and can watch the coolant temp, I won't have to worry about it. and can actually watch the differences.

Edit: It was 9 deg this morning and I'm losing about 20% over my summer milage so if this really work that well I'll be quite happy.

 

I have been pretty much blocking the whole thing.
Over the highway, at 70 MPH, in 50 degrees, I noticed the water temperature rise about 20 degrees, more than I'm comfortable with. No "warnings" have ever come on.

At slower speeds, the engine is not working as hard, and the water only runs 1 or 2 degrees warmer. But the warm up time from a cold start is cut in half.

In stop and go, you want you engine to go off, right? Each time it is off, it is a cool down period. You have almost zero chance of overheat in stop and go, because your engine ( Hopefully ) is off more than half of the time.

Notice I said "time".
You cannot drive with battery for more than half of the miles, but if you are standing still a lot, you can run off battery for half or more of the TIME.

Good luck!
-John

 

How and where do you attach the cardboard? Do you attach it directly to the radiator, or do you cover the air intakes?

If it's cardboard, doesn't it get ruined in the rain?

Thanks for the help.

 

Actually the cardboard was temporary, just to see how it worked.
Cardboard is remarkably resiliant, but I also live in a dry climate.

After a few weeks of no overheat, I replaced the cardboard with a 1/2" thick sheet of styrofoam that came in the crate with a coffee table. I figured it is waterproof, and won't hold the water so ( hopefully ) won't mold or mildew.

I considered using clear plexiglas to make it look more "invisible"... but that costs $ and the styrofoam came free with the table!
( plus if you put too much money into it, it defeats the purpose of trying to save money by burning less gas, right? )

If you unscrew the plastic honeycomb grill cover at the top ( 2 hex screws ) and, unscrew the hood release lever ( one torx "star" screw ), this makes life easy to slip something in front.

You can wedge or "clamp" the material in the plastic grill cover when you screw it back on. Since all the wind pressure is just pushing it against the radiator, it really has no where to go. And since it was free material, I won't be sad if it ever does fall out, as long as I don't get a littering ticket, but I don't really think this is possible unless it breaks into little pieces.

The cardboard was only loosely wedged in there, and didn't budge in 2 months, 4,000 miles. The cardboard test did not cover 100% of the surface... maybe 80% and no overheat in Fall. ( Oct to Dec. )

Now, it is covered 100%, but it's the coldest part of the year now.

Word of caution:
There are 2 radiators... one for the engine, and one for the electric parts.
While I can monitor the engine temperature with a scangauge or on-board display, there is no way to directly monitor the electronics. A warning lamp will light on the dash if any part gets too hot. Thankfully, that has never happened.
I drive more gently than most.
If you drive fast, or have demanding conditions, or daytime highs that hit 60, then consider only a partial block. Also make sure other drivers are aware of this "modification".

Let me know how it goes!
-John

 

It'll be this weekend before I get around to it, but I'll let you know.

 

I also made temporary cardboard panels to test with and I had 100% coverage on both the grille and the lower opening. It helped my milage by at least 2 MPG over the first 100 miles on this tank. I monitored the engine temp on my 60 mile commute and it got up to 105C, which I think is a bit high. Anyone have numbers to compare? I never got any overtemp lights, but the heater smelled pretty hot so I ended up taking the lower panel back off. The temperatures went back up this morning so it's getting difficult to gauge how well the changes are working. I'm going to leave it like this for a few days and see how it averages out.

 

Although I haven't made the panels yet, I'm in the same boat. It warmed up to the 50s here today. I've wanted to know what the normal operating temperature was so I could size the panels apropriately, so I've been using the test mode of the instrument panel LCD. Right now I really only have cold days on my 1.6 mile commute to compare, and then it never got over 80 C, but the ICE never shut down either.

So, if anyone does have the standard operating temperature, I would love to know it!

 

Without any cardboard blocking, my scangauge is reading an average of 185 F which is about 85 C. That's my average for a 45 minute drive when the outside temp was 33 F.
Hope that helps. Isn't the cooling system thermostat a 180 F thermostat?