Deck Plate Mod....For Increased Cold Weather MPG

[jonshonda]

I think it is an interesting experiment, and am curious what you find out. Have you already removed your roof rails?
If you are already getting 18.5 mpg (U.S. mpg, calculated using distance / gallons, not relying on the display in the car) then you are already doing way better than average. With that kind of fuel economy, your range would be well over 200 miles. I just don't see how you could realistically expect to improve on that. But I am interested in reading about it, so continue on.

My suggestions to improve fuel economy would be :
block heater (to reduce warmup enrichment time)
0w-30 oil with ceratec additive
krytox in all wheel bearings
electric cooling fan
turn off A/C
etc. etc.

I like your thoughts on the block heater, tell me more about the ceratec additive please.

I don't plan on removing anything or modifying oils to improve mileage, this is just a winter experiment for now.

I'm all for cool experiments, but doesn't adding all this stuff sort of out weight the cost of the fuel savings? Haha, like "I saved $200 on gas this winter! Only cost me $300!"

Uhhh, the grill blocks were free, and the deck plate mod might cost me $25?

I do not understand how u get better MPG with warmer air. Cold air is denser, which provides more power. Similar to driving at a lower elevation. If u have more power, but still drive the same speed as summer time, it should thus require less throttle to maintain that speed, and thus give the same MPG. Either way your chasing .5 MPG better mileage, and gas is cheap right now. I would focus your time on something else. The few years gas was really expensive 5 years ago, made many people very worried about MPG. Some still are even though gas is cheap.

Think of it this way, the same volume of air is drawn into a cylinder during the intake stroke, and in order for complete combustion to happen fuel trims need to be adjusted according to air temp (colder air requires more fuel because it is more dense than warm air). You are correct saying that colder air makes more power, but it doesn't just happen w/o a direct correlation with more fuel. You cannot just add more fuel to warm air and expect more power, as you would run rich do to incomplete combustion. But you can dump more fuel w/ cold air and to create more power and still have ideal mixtures/combustion.

There is also a reason people put grill blocks on in colder climates. Engines have an ideal operating temp range. Too hot or too cold and you out not at peak efficiency. Along with aerodynamic improvements from blocking the grill, you will increase engine efficiency by allowing your engine to stay warmer in cold conditions.

My goal isn't 0.5 mpg improvements, it is to retain my warm weather fuel efficiency during the winter months. I don't know how the GX470 operates in the cold, but as I stated in the OP I was able to overcome 3-4mpg decreases in cold weather on my 02 CRV by blocking my grill and drawing in warm air.

 

[White Stripe]

I like your thoughts on the block heater, tell me more about the ceratec additive please.

I don't plan on removing anything or modifying oils to improve mileage, this is just a winter experiment for now.



Uhhh, the grill blocks were free, and the deck plate mod might cost me $25?



Think of it this way, the same volume of air is drawn into a cylinder during the intake stroke, and in order for complete combustion to happen fuel trims need to be adjusted according to air temp (colder air requires more fuel because it is more dense than warm air). You are correct saying that colder air makes more power, but it doesn't just happen w/o a direct correlation with more fuel. You cannot just add more fuel to warm air and expect more power, as you would run rich do to incomplete combustion. But you can dump more fuel w/ cold air and to create more power and still have ideal mixtures/combustion.

There is also a reason people put grill blocks on in colder climates. Engines have an ideal operating temp range. Too hot or too cold and you out not at peak efficiency. Along with aerodynamic improvements from blocking the grill, you will increase engine efficiency by allowing your engine to stay warmer in cold conditions.

My goal isn't 0.5 mpg improvements, it is to retain my warm weather fuel efficiency during the winter months. I don't know how the GX470 operates in the cold, but as I stated in the OP I was able to overcome 3-4mpg decreases in cold weather on my 02 CRV by blocking my grill and drawing in warm air.

No I'm saying if u make more hp with cold air, then it takes less throttle to maintain say for example 60mph during the cold then it would if the air was warm , less dense. So it should be a wash in the end. The reason people cover there grill in the winter is because it's so cold the engine isn't getting hot, thus making for no heat through the heater.

 

[04UZJ100]

You won't notice any difference. If a minute difference in fuel economy is important to you, you're driving the wrong car.

 

[jonshonda]

You won't notice any difference. If a minute difference in fuel economy is important to you, you're driving the wrong car.

Well aren't you just a peach. Every penny I save in fuel I can spend on fun mods. Now I just want to do it to watch people like you eat crow.

Being an engineer I am used to the negative attitudes towards change. If nothing else, people like you are what inspire people like me to try new things. I do it just to prove them wrong...then I rub their nose in it!

 

[04UZJ100]

Well aren't you just a peach. Every penny I save in fuel I can spend on fun mods. Now I just want to do it to watch people like you eat crow.

Being an engineer I am used to the negative attitudes towards change. If nothing else, people like you are what inspire people like me to try new things. I do it just to prove them wrong...then I rub their nose in it!

I'm an engineer too. Good luck. Have fun.

 

[jonshonda]

No I'm saying if u make more hp with cold air, then it takes less throttle to maintain say for example 60mph during the cold then it would if the air was warm , less dense. So it should be a wash in the end. The reason people cover there grill in the winter is because it's so cold the engine isn't getting hot, thus making for no heat through the heater.

You are correct that cold air makes more power, thus requiring a smaller volume of cold air to create the same power required with hot air. In theory that means the throttle body plate is restricting the amount of air coming into the cylinders, which is where the pumping loses become a factor. Power is required to overcome the restrictions created by the throttle not open as far. More power is required to suck air through a smaller opening.
I have no idea if this will work, as different cars react differently to WAI than others.

But what I do know WILL work is blocking the grills. Allowing the engine to warm up faster will decrease the amount of time it will be running rich after a cold start, and keeping the engine warmer will allow it to operate more efficiently. Think about the transmission fluid too, blocking the grill will allow the trans fluid to run much warmer, meaning there will be less from cold fluid.

 

[langsen]

I think you want an electric fan with a good fan controller. This would give you the most improvement in fuel economy without getting too crazy. A Ford Contour fan might work.

If the warm air intake would make such a difference, I find it hard to believe that Toyota would not have done it initially. What are the reasons not to do it?

 

[BlackCat]

I think you want an electric fan with a good fan controller. This would give you the most improvement in fuel economy without getting too crazy. A Ford Contour fan might work.

If the warm air intake would make such a difference, I find it hard to believe that Toyota would not have done it initially. What are the reasons not to do it?

Umm, summer?

 

[JLee]

You are correct that cold air makes more power, thus requiring a smaller volume of cold air to create the same power required with hot air. In theory that means the throttle body plate is restricting the amount of air coming into the cylinders, which is where the pumping loses become a factor. Power is required to overcome the restrictions created by the throttle not open as far. More power is required to suck air through a smaller opening.
I have no idea if this will work, as different cars react differently to WAI than others.

But what I do know WILL work is blocking the grills. Allowing the engine to warm up faster will decrease the amount of time it will be running rich after a cold start, and keeping the engine warmer will allow it to operate more efficiently. Think about the transmission fluid too, blocking the grill will allow the trans fluid to run much warmer, meaning there will be less from cold fluid.

The thermostat is closed until the engine reaches operating temperature - how does blocking the grill accelerate this process by any meaningful amount?

 

[jonshonda]

The thermostat is closed until the engine reaches operating temperature - how does blocking the grill accelerate this process by any meaningful amount?

Is this a trick question?

 

[BlackCat]

Is this a trick question?

Since you appear to just like to tinker with stuff because it's fun, have you looked into a unichip? It would allow you to tune the truck to your liking.

 

[JLee]

Is this a trick question?

No. You have no coolant movement through the radiator until coolant has warmed to the point where the thermostat opens. Unless I'm wildly underestimating the cooling effect of air passing over the outside of the engine, I am not sure what I'm missing here.

 

[jonshonda]

Since you appear to just like to tinker with stuff because it's fun, have you looked into a unichip? It would allow you to tune the truck to your liking.

NEVER!! haha

No. You have no coolant movement through the radiator until coolant has warmed to the point where the thermostat opens. Unless I'm wildly underestimating the cooling effect of air passing over the outside of the engine, I am not sure what I'm missing here.

What was interesting about the grill block and my past experience w/ my CRV, was that I was able to see every time the thermostat opened due to the fact the intake was right above the radiator. My intake temps would increase very quickly when it opened, then decrease when it closed again. I would say that at zero degrees even with the grills on my CRV 85% blocked, the thermostat wouldn't open up once during a 100 mile commute, *maybe* if I was sitting at a stop lot for a while after coming off the interstate.

Otherwise cruising at 65mph on fairly hilly terrain with a few passengers at below 10 degrees typically meant the thermostat never opened. Remember running your heater is also aiding in taking heat out of the coolant. So I would say yes, you are vastly underestimating the cooling affect of air coming into the engine bay at 65mph.

 

[chitown40]

I'm not a hater, but I can be a skeptic at times.

I see "potentially" the value of a grill block during extreme cold weather, on an extended drive at highway speeds while using the heating system. I'd have to start monitoring the coolant temps via Techstream or Torque to really see if there's a signifcant difference. 18.5 MPG may be what you are getting in the summer at 99% highway driving, but in my experience with the GX, once you get into traffic or city driving, the MPG tanks back to 14-15.

Diesel engines tend to run cooler and are more likely to need a grill block in the winter to keep their operating temps in range.

 

[jonshonda]

I'm not a hater, but I can be a skeptic at times.

I see "potentially" the value of a grill block during extreme cold weather, on an extended drive at highway speeds while using the heating system. I'd have to start monitoring the coolant temps via Techstream or Torque to really see if there's a signifcant difference. 18.5 MPG may be what you are getting in the summer at 99% highway driving, but in my experience with the GX, once you get into traffic or city driving, the MPG tanks back to 14-15.

Diesel engines tend to run cooler and are more likely to need a grill block in the winter to keep their operating temps in range.

I 100% understand and respect your skepticism. Grill blocks would be an aerodynamic benefit on a lot of vehicles year round. Look at Nascar for a perfect example of the aero advantage of blocking the grill. You will see their grills all taped up to allow the air to move around or over the car, instead of making its way into the engine bay causing turbulence.

Another experiment I tried was an air dam on my CRV. It was roughly 8" tall and extended just below the lowest part of the undercarriage. I picked up 1-2mph on average with the air damn.

I understand and accept the criticism behind trying to improve the mpg of a rolling brick. This is just an experiment and gives me something to do in the cold and sometimes boring winter months in WI. I already have the torque app on my phone, and an Bluetooth OBD2 adapter, so minimal investment for the entertainment value.

 

[co4wheel]

Just be careful. I have a diesel. I block part of the grill when it's SUPER cold. It needs a little help when it's -10F. But as soon as it gets back to 20F or above off it comes. To much risk in overheating a very expensive engine it I forget it's in place. The Lexus is gas. It heats up so easy. It's just not much of a concern. You could block part of the grill. But the idea/risk of forgetting it's in place, hitting the higher temp and causing a issue is HUGE. OEM temp gauges are useless. They are buffered to indicate MIDDLE once the temp hits Warm and stay in the middle all the way until the car is dangerously HOT. Don't trust it for this type of stuff. If your not getting a way to read actually fluid Temp don't start blocking the radiator IMHO. On a diesel it's a little easier. In -10F weather your lucky to get heat. So you kinda know you need to block the radiator. Different world all together.

 

[jonshonda]

Me thinks you didn't read the part where I said I have obd2 Reader and app on my phone?

 

[co4wheel]

Me thinks you didn't read the part where I said I have obd2 Reader and app on my phone?

Cool. But I would suggest a real gauge if your leaving the radiator blocked for any extended period of time. Something you see if your driving around and your temp is creeping up. Not looking at your phone.

 

[jonshonda]

Cool. But I would suggest a real gauge if your leaving the radiator blocked for any extended period of time. Something you see if your driving around and your temp is creeping up. Not looking at your phone.

Bluetooth OBD2 adapter takes real time info right from the ECU and displays it on my phone. Readings displayed to 1/10th of a degree. Read up on it maybe, it might help clear up some confusion.

 

[co4wheel]

Bluetooth OBD2 adapter takes real time info right from the ECU and displays it on my phone. Readings displayed to 1/10th of a degree. Read up on it maybe, it might help clear up some confusion.

Not confused. Your missing my point. It's a HUGE safety issue to not know what is going on with the engine in a easy to see manner. Looking at your phone is NOT the solution in the long term if you are actually going to do this. You need a real gauge, in your line of sight all the time. Blocking the radiator is DANGEROUS IMHO. You need proper precautions. There are even OBD2 electric gauges that are small can can be mounted on the dash. My buddy had one on this track car years ago.