Preparing for winter with a comprehensive strategy to improve MPGs including grille blocking & more

[hybridbear]

I have been doing a lot of general research to prepare for this winter with a comprehensive winter weather strategy to see the least decrease in fuel economy.

 

Part 1: Grille blocking

Last year acdii made a grille cover, see this thread, which he then kindly sent me as a gift after he got rid of his first FFH, the Blue Devil.

I ran out of zip ties so I bought more on Amazon planning to put this cover on soon as temps are now consistently below 50^oF. Since the temps dropped last week I've seen a marked drop in fuel efficiency. Trips that used to consistently get 60-65 MPG now are only seeing 50-55. My current tank average has dropped from about 57.5 MPG over the first 200 miles to now 56 MPG over 275 miles. These last 75 miles have taken a big toll on my fuel economy averaging only around 52 MPG. Unfortunately, the zip ties I bought are being shipped from China. I'm am quite annoyed at Amazon that nothing prior to purchase indicated that they would be shipped from China and that they would take 3 weeks to arrive. I expected them to come like most Amazon items in about 1 week or less. So while I'm stuck waiting I decided to do more research.

 

Grille blocking is useful to help the ICE warm up faster and to insulate it to keep it warm longer. The cold winter air flowing over the radiator and engine compartment while you drive quickly sucks the thermal energy out of the components that you want to stay warm for maximum efficiency. Since the FFH is designed to spend a large percentage of its miles with the ICE off this is a problem in winter.

 

However, you do not want to block the flow of cold air to the electric components. While the ICE is less efficient in the cold, the hybrid computer and electric components are not adversely affected by the cold. In fact, you want to keep those components as cool as possible to keep them from wearing out. Thus it is important to understand where the radiator is for the hybrid system and not block its airflow.

 

In the FFH you'll see that there are two radiators. A large one with a fan, for the ICE, and a small one that is in front (closer to the grille) than the large one. The small one is for the hybrid components. In the FFH it is located down low and receives its airflow from the lower grille opening. The ICE radiator spans the entire height and gets airflow from both the large upper grille and the lower grille. In my past experiences with using acdii's grille cover on the upper grille (see this thread) I found that even in the summer the ICE didn't get too hot with the upper grille blocked. However, I didn't leave it on because I was concerned that the electronics would get too hot from the limited airflow through the engine compartment even though the inverter radiator being still exposed to air.

 

Sadly, there is no way currently to monitor the temp of the inverter coolant. Hopefully someone brilliant will figure out the XGauge coding for that soon.

 

Thus, my plan for this winter is to use acdii's grille cover on the top grille while temperatures are consistently below 50^oF. Once the temperatures drop down below freezing I may block one row of the lower grille. I do not want to block any more of that lower grille to keep the electric components as cool as possible.

 

I discovered that as soon as the car is turned on the coolant is flowing through the inverter radiator. Even though the ICE was not very warm and the inverter coolant was barely warmer than room temperature the coolant was constantly flowing while the car was in park sitting in the garage in my tests this evening. I want to further test this when the car has been sitting for hours and the ICE/inverter components are completely cold but it seems likely that this coolant will circulate non-stop when the car is on regardless of temperature. For this reason I don't want to interfere with that by blocking the lower grille except partially in extreme cold. The reason to consider partially blocking the lower grille in extreme cold is because the ICE is still cooled by that grille and in extreme cold blocking the upper grille only might not be enough to keep the ICE warm.

 

The common Prius grille blocking links talk about only blocking the lower grille on the current gen Prius since its inverter radiator is located up high. The Prius also appears to constantly circulate the inverter coolant anytime the car is turned on regardless of temperature.

 

Part 2: Use the heated seats

Instead of turning on the HVAC right away when the ICE is cold I plan to use the heated seats for initial warmth. Turning on the heated seats will not make the ICE come on like turning on the HVAC will. On low each heated seat draws about .13 amps from the HVB or 0.0364 kW. This is a minimal power draw, less than the headlamps.

 

Part 3: Intelligent HVAC use

I use "intelligent" here to mean that I'm applying my knowledge of the FFH's inner workings to how I control the HVAC settings.

 

Since below a certain coolant temp threshold the ICE will run constantly to make heat I don't want to turn the HVAC on until the coolant temp is warm enough not to interfere with normal operation. Since the PCM update modified these settings I don't know yet what that temperature is. I also plan to not set the HVAC temp any higher than absolutely necessary.

 

Parts 2 & 3 will improve efficiency by not causing the ICE to run only to make heat which is not efficient. Part 1 improves efficiency by getting the ICE warm faster and keeping it warm longer.

 

I don't sacrifice much personal comfort to do this since in the winter I'm already dressed for being outside and don't need much heat anyway. When leaving from home our car is also parked in a heated garage so we always get into a warm car at the start. In any car you wouldn't have heat immediately so turning on the HVAC on from the start does no good. With the grille blocking strategy I hope to dramatically lessen the ICE warm up time so that the delay compared to a gas only car is minimal.

 

I wanted to share this strategy so that others can consider implementing any of the above steps or adding their own suggestions. Once I know the minimum coolant temp to turn the ICE off and still have heat I will add it.

[lolder]

There are three radiators in the Gen 1 FFH, the Electric, AC and engine cooling in that order front to back. Why are the automatic slats not enough in the Gen 2s?

[murphy]

Blocking the radiator should not cause the engine to warm up any faster assuming there is a working thermostat in the radiator to prevent coolant flow until the coolant reaches the thermostat's set point. In a car this computerized I would expect the thermostat to be replaced by a computer controlled water valve though.

 

Does anyone have access to a shop manual to see what is actually in the engine cooling loop?

[lolder]

I think it's a computer controlled water valve. They had a programming change because of overheating in one of the Ford models within the last year.

[hybridbear]

Blocking the radiator should not cause the engine to warm up any faster assuming there is a working thermostat in the radiator to prevent coolant flow until the coolant reaches the thermostat's set point. In a car this computerized I would expect the thermostat to be replaced by a computer controlled water valve though.

 

Does anyone have access to a shop manual to see what is actually in the engine cooling loop?

As soon as the ICE turns on there is coolant flow somewhere. This can be seen by the fact that the coolant temp according to ET Mode will remain steady when driving in EV, but as soon as the ICE turns on the coolant starts circulating and drops in temperature. In cold weather this drop is up to 10^oC (18^oF). This is a big drop that happens as soon as the ICE comes on and it takes a long time of running the ICE to regain that warmth. Blocking the upper grille lessens this drop by slowing the flow of cold air into the engine compartment.

 

There are three radiators in the Gen 1 FFH, the Electric, AC and engine cooling in that order front to back. Why are the automatic slats not enough in the Gen 2s?

The grille shutters don't do enough to block the air flow because they are behind the grille. That air is still getting into the engine compartment around them. The air just hits the grille shutters and bounces around them. By putting a cover on the outside of the grille I'm able to only let a much smaller airflow get in around the edges of the cover. Acdii showed last year that having the grille cover on his defective BD car make it warm up much faster from a cold start and kept the car warm longer when driving in EV mode.

 

I will look again to figure out where the third radiator is for the AC.

Edited October 16, 2013 by hybridbear

[acdii]

Blocking the radiator should not cause the engine to warm up any faster assuming there is a working thermostat in the radiator to prevent coolant flow until the coolant reaches the thermostat's set point. In a car this computerized I would expect the thermostat to be replaced by a computer controlled water valve though.

 

Does anyone have access to a shop manual to see what is actually in the engine cooling loop?

Oh yes it DOES! Believe me on this one! Many here know my woes when I had the BD, and how crappy it ran on cold days. I would drive 1 hour to work with cold feet. As soon as I put the upper grill cover on I had HEAT! It cut the EV wait cycle in half. On cold days below 32* the ICE warms up before it would allow EV mode(whether or not the update changed that, wont know until its cold again). I would normally drive 5 miles before it would go to EV mode, after putting the cover on I could get EV in 2 miles. Also keep in mind, right at the end of my driveway, its rural highway speeds of 55 MPH. I'm pretty certain the low coolant temps led to the plug fouling too, but have nothing to prove it.

 

Pre-cover the ICE would not get to 180* unless it heat soaked at a light, and once moving again, and go into EV would drop to 160*. Post-cover, it would get to 180* and stay there. It did help improve MPG by 2 MPG, so instead of getting 34, it got 36.

 

I did find that putting lower cover on made no difference, so I wont be making a lower one for the HyTi.

 

HB, do you have a Harbor Freight nearby? They have a cable tie container for like $5 with a ton of ties in it of various lengths and in black and white.

[KLH]

If I understand the key value of the grill block, it's that the grill block prevents the ICE from cooling down during cold temperature driving. Reasoning this out, I would assume that this would be more of an issue for city driving, where the ICE may frequently be off (thus cooling down).

 

In highway driving, do you perceive the grill cover impacting MPG since the ICE is basically always on at 60+ mph?

[acdii]

 

In highway driving, do you perceive the grill cover impacting MPG since the ICE is basically always on at 60+ mph?

Nope, it is a gain since it keeps the airflow away from the radiator so that it maintains the temps during the EV cycles. It also improves aerodynamics more than the shutters can. When you are traveling at 60 MPH the airflow into the radiator drops coolant temps extremely fast, even with shutters closed, so every time the thermostat opens an inrush of cold coolant gets into the ICE and it has to use more fuel to raise the temp back up. It becomes a vicious cycle when its 20* or below out. The Fusion's cooling system is hyper efficient, meaning it keeps the ICE very cool running when on the highway, mainly due to heat soaking that happens in city driving when it does more EV/ICE cycling. If you were to hook up a scan gauge and watch the engine temps while driving it will become very apparent what I mean. When I was monitoring the BD during some cold driving, the temp would get up to about 160* while cruising at 55 MPH, then during an extended EV cycle going down a long hill, the temp would drop to 120*. When sitting at a light after being on ICE, the temp would rise to 180*, and drop down to 160* once I start moving again.

 

After I put the cover on, the temp was much more stable, but still took quite some time before it reached full operating temp of 180*, and during heat soak would get near 200*. From what I have read from others, the ideal ICE temp is right around 200* for the best efficiency. The BD NEVER got that high unless it sat after driving at least 10 miles, and would drop down to 180 as soon as the ICE started up again.

 

OTOH I never needed covers for the 2010 FFH. It always had heat in the winter and always did really good MPG. It averaged between 34 and 36 in the winter, and low 40's in summer, right where the EPA said it would. If I did put a cover on it, it might have done a little better in the winter, but even so I was OK with what it was getting. It was less than a 10% variance over EPA. Much better than the 30%+ the other car was doing. Keeping my fingers crossed that I wont be seeing such a drastic change when it gets cold here in the HyTi, and very optimistic about it based on the few cold morning we have had recently in the 40's and I still am getting 45 MPG.

 

 

Now if only every trip was 45 MPG, but alas, not every trip is perfect. Some days I just dont feel like playing the game.

 

Oh here's a tip for you all, if you are accustomed to wearing thin soled shoes while driving, putting on thick soled shoes, like work or hiking boots, you can expect to have lower MPG. :) For some odd reason I found it much harder to drive when I couldnt feel the pedals. LOL

[milleron]

Paul Jones, the C-Max owner who's posted results on our sister forum about grill covers, actually manufactures them for the C-Max. As the FFH grill is similarly shaped and just a bit larger, he's interested in making winter grill covers for our cars, as well. He informs me that attachment on the Fusion grill is a bit of a problem, at least when trying to use the same method employed on the C-Max covers. He's hoping to find a FFH owner in the Atlanta area who's interested in obtaining grill covers and who might work with him a little on it. He didn't say this, but I'm guessing that that person would get a sweat-equity discount on the first cover he makes..

 

Judging from my frustrating experience just trying to drill simple screw holes in this type of plastic, I'd gladly pay the $100 he asks for his C-Max covers if I could buy them.

 

Anyone wishing to correspond with Paul about this should contact him directly at paul@star-instruments.com or call him at work at (770) 683-9177

Anyone who would be willing to give him some photos and ideas about their method of attachment with cable ties, please do so. Winter's fast approaching.

[Da0ne]

Judging from my frustrating experience just trying to drill simple screw holes in this type of plastic, I'd gladly pay the $100 he asks for his C-Max covers if I could buy them.

 

 

i would like to do the same especially here in New york where i have seen the FFH take a hit because of the cold weather

[keithsm2]

ACDII...I have a question about scan guages.. I understand you are taking a temp reading with it and monitoring while you are driving.... I assume it is taking this temp from just ONE point somewhere in the System? If the ice is not on and there is no circulation .....is it possible the " whole" system is not seeing the temp. drop you are describing?

[acdii]

From my understanding, the temp of the ICE is taken pre-thermostat, so it measures the ICE temp. This is the important one for Engine operation. I haven't hooked the SG up to the new car yet to see how it is with the cover on, but will dig it out when I remember to. My cover works quite well, and isn't very hard to attach.

 

Here is the one I gave to HB, the one I made is nearly identical, I just drilled the holes different.

 

 

I found the lower one isnt needed, didnt make any difference with it on or off. I attached the cover with cable ties. My new one I drilled the lower holes for the bottom grill bar without realizing that there is solid plastic there, so had to drill holes in the gril to match. No biggy, cat see them unless you are on the ground looking up.

[milleron]

acdii, what's the material? polycarbonate? Where did you buy it, and what did you use to cut it? I seem to recall your saying you use some sort of blade on a Dremel tool; is that correct? Do they perhaps make saber-saw blades for plastic like that?

 

Would you mind emailing that photo to Paul Jones? His email address is in my last post.

[hybridbear]

ACDII...I have a question about scan guages.. I understand you are taking a temp reading with it and monitoring while you are driving.... I assume it is taking this temp from just ONE point somewhere in the System? If the ice is not on and there is no circulation .....is it possible the " whole" system is not seeing the temp. drop you are describing?

I referenced the temp drop of the coolant here too. It appears that anytime the ICE is on the coolant is circulating, even when the ICE is cold. When the ICE is off the coolant sits. What happens is that the coolant that is far away from the temp sensor cools down much more than the coolant at the temp sensor. This leads to the coolant temp dropping rapidly when the ICE first turns on. In my drives yesterday I found that it takes acceleration up to 35-40 MPH plus multiple blocks of driving to recover this lost heat from EV driving without a cover. Today I put the top cover back on. I created a spreadsheet for tracking trips that I will use to gather data.

[lolder]

I've mentioned before that you don't know the temperature of the electronics. These cars are delicate compromises so be careful with the covers. As an analogy, if you have a refrigerator/freezer with the temperature sensor in the refrigerator and a mechanical vent between the sections, if you run it in a house with the winter thermostat set to 50º F., the freezer will defrost. The unit will not run enough. The car is designed for certain temperature ranges and air flows. It would not be good to fry the very expensive electronics. They may be cooled enough but how can you tell ? I presume the radiator fan shuts off with higher vehicle speed. What will draw air over the electronics radiator then? The electronics is always doing the same amount of work.

[hybridbear]

I've mentioned before that you don't know the temperature of the electronics. These cars are delicate compromises so be careful with the covers. As an analogy, if you have a refrigerator/freezer with the temperature sensor in the refrigerator and a mechanical vent between the sections, if you run it in a house with the winter thermostat set to 50º F., the freezer will defrost. The unit will not run enough. The car is designed for certain temperature ranges and air flows. It would not be good to fry the very expensive electronics. They may be cooled enough but how can you tell ? I presume the radiator fan shuts off with higher vehicle speed. What will draw air over the electronics radiator then? The electronics is always doing the same amount of work.

That is why I don't block the lower grille which is where the radiator is for the electronics. As I said before, the coolant is always circulating through that radiator anytime the car is on. There is no fan for that radiator so the electronics are never cooled by a fan drawing air across the radiator. The radiator fan in the 2013 is quite small and is located high up on the ICE radiator. ptjones has observed that the fan doesn't come on until the coolant temp reaches 212+^oF. Even will the top grille covered in the summer our car never got anywhere near that warm. For the bottom grille the grille shutters are enough insulation. Presumably Ford has programmed the shutters to not block the air from getting to the electronics radiator when needed. The fact that Ford puts grille shutters in front of that radiator which are closed almost all the time shows that in most conditions there is still plenty of air flow.

 

I agree that it is extremely important to keep the electronics cool. In Florida where you live I'm sure you would never block the grille. But in Minnesota where our weather doesn't go above 32^oF for months at a time this isn't an issue because the air is so cold. I drove a number of miles yesterday starting cold with the HVB showing a temp of about 41 degrees (ambient air temp), even with driving for more than 30 minutes the HVB temp only reached about 62 degrees without the fans coming on at all to cool it. When the weather gets colder the HVB will be much colder.

 

Do you think the electronics under the hood would heat up faster than the HVB when the under hood parts have coolant flowing non-stop?

Edited October 22, 2013 by hybridbear

[lolder]

I don't know the answers. I can conceive of an early Spring day up there where the temperature goes to 75 and you turn the AC on in a car sitting in the Sun and the cover is still on and you forget about it. I believe there is a message center warning for electronics over-heat. I'm an experimenter too but be careful. This is not your Daddy's Ford.

Forty years ago I did some modifications to a '68 Volvo cooling fan circuit and ended up blowing a fuse plug out of the AC condenser from overheating. I forgot about idling or something like that.

I'm wrestling with 89º temps today moving my DSL modem around the house and outside to the service box trying to improve my DSL signal to noise ratio. The service box is right in the afternoon Sun in some bushes. Life's a beach.

Edited October 22, 2013 by lolder

[acdii]

acdii, what's the material? polycarbonate? Where did you buy it, and what did you use to cut it? I seem to recall your saying you use some sort of blade on a Dremel tool; is that correct? Do they perhaps make saber-saw blades for plastic like that?

 

Would you mind emailing that photo to Paul Jones? His email address is in my last post.

I use a bandsaw and belt sander. I can make one in 30 minutes. With a template I can make 10 or more an hour. I used a low end poly carbonate that can crack easily sine it was an experiment. If I were to make some for sale I would use a more crack resistant plastic.

 

 

They are easy to make but a bugger to ship, They are thin, but long and fragile. The one I shipped HB I used the box from one of my RC planes.

[ptjones]

I use a bandsaw and belt sander. I can make one in 30 minutes. With a template I can make 10 or more an hour. I used a low end poly carbonate that can crack easily sine it was an experiment. If I were to make some for sale I would use a more crack resistant plastic.

 

 

They are easy to make but a bugger to ship, They are thin, but long and fragile. The one I shipped HB I used the box from one of my RC planes.

That is why I use LEXAN type plastic, It's more expensive but it doesn't break. I used mine all year long with no problems. BTW my current record is 63.4MPG, 875mi, 13.8gal on a trip to FL and back.

Paul

Paul

[Da0ne]

That is why I use LEXAN type plastic, It's more expensive but it doesn't break. I used mine all year long with no problems. BTW my current record is 63.4MPG, 875mi, 13.8gal on a trip to FL and back.

Paul

Paul

 

nice record

 

well if either you or acdii decide to make one for the fusion sign me up already starting to see a decline in mpg

[milleron]

Acrylic is not dirt cheap.

Lexan is pretty darned expensive, especially considering that when you buy a piece as big as a FFH grill, there's a lot of waste.

 

Which is more cost-effective in the end?

Which is easier to cut and drill?

 

I've found a plastic fabricating company near my home, and I'm in the process of finding what they'll charge to cut out a cover using a paper template I'll supply them. I'll post this information here, but if it's too dear, I'll probably attempt to make an acrylic one myself. The trouble is that it's so difficult to work with that stuff without it cracking. I kind of dread trying it.

[ptjones]

Acrylic is not dirt cheap.

Lexan is pretty darned expensive, especially considering that when you buy a piece as big as a FFH grill, there's a lot of waste.

 

Which is more cost-effective in the end?

Which is easier to cut and drill?

 

I've found a plastic fabricating company near my home, and I'm in the process of finding what they'll charge to cut out a cover using a paper template I'll supply them. I'll post this information here, but if it's too dear, I'll probably attempt to make an acrylic one myself. The trouble is that it's so difficult to work with that stuff without it cracking. I kind of dread trying it.

LEXAN doesn't crack and is easy to work with. I'm currently selling CMAX covers for $100+ shipping. I had a prototype but didn't have car to put it on.

Paul

[milleron]

That is why I use LEXAN type plastic, It's more expensive but it doesn't break. I used mine all year long with no problems. BTW my current record is 63.4MPG, 875mi, 13.8gal on a trip to FL and back.

Paul

 

 

Paul,

 

I'm thinking that there's enough of a market here for you to perhaps just check out a FFH at the local Ford dealer to get a template.

As owners here have had great luck mounting with cable ties, I imagine that most of us could get them mounted ourselves.

Have you given any thought to making the cover in two pieces, split vertically right down the middle, to make shipping easier. That could work, as the halves could be mounted independently with cable ties. If there was air infiltration through the remaining crack, it could be completely corrected with a narrow piece of clear tape. Just setting up a "straw man" to see if anyone wants to knock him down.

[ptjones]

 

Paul,

 

I'm thinking that there's enough of a market here for you to perhaps just check out a FFH at the local Ford dealer to get a template.

As owners here have had great luck mounting with cable ties, I imagine that most of us could get them mounted ourselves.

Have you given any thought to making the cover in two pieces, split vertically right down the middle, to make shipping easier. That could work, as the halves could be mounted independently with cable ties. If there was air infiltration through the remaining crack, it could be completely corrected with a narrow piece of clear tape. Just setting up a "straw man" to see if anyone wants to knock him down.

I could make some Grill Covers if a enough members were interested. I thinking $75 for both Grill Covers including shipping by USmail. I will need to order some LEXAN type material and shipping as one piece is not a problem. You need to figure out away of mounting them for the time being until I can come up with a better solution. You email me at paul@star-instruments.com if you are interested.

[milleron]

Paul,

 

I know for a fact that $75 is an extremely fair price. Please sign me up. Of course, I'm willing to pre-pay.

 

I'd ask the moderators, hybridbear and acdii, if there's a way to get Paul's proposal posted more widely than it is now on this particular thread?

 

Ron