Engine Insulation

[GdB]

I always drive short distances and get bad mileage because half the time I'm warming up with rich mixture, high idle...

All the aero mods are pretty neat, but would not help me too much. After I read this article I thought maybe I should try it and see if I notice much difference:

BMW is looking into insulating engines...
Green Car Congress: BMW Outlines Intelligent Heat Management Applications for Reducing Fuel Consumption and CO2; New Thermoelectric Generator Unit Integrated with EGR

A great deal of thermal energy is generated while driving and is available after coming to a stop—energy stored in components such as the engine and transmission. The engineers are therefore seeking to prevent the engine from cooling down quickly and to retain as much residual heat as possible so that the engine is not completely cold when started the next time. Particularly under realistic customer driving conditions, this can contribute to a significant reduction of fuel consumption.
To keep temperatures within the engine compartment at a high level for as long as possible and to avoid having to warm up the engine from the regular ambient temperature, the engine is fully encapsulated. In addition to the air flaps behind the BMW kidney grille already introduced in 2007 in the context of BMW EfficientDynamics, an engine on a prototype that is already developed is completely surrounded by fully clad walls and panels, the engineers using proven materials from the underfloor of the car for insulation purposes.
Components in the engine compartment which previously had to be cooled at a great effort are now protected better from engine heat by the encapsulation. With encapsulation, an engine running at a temperature of 80 °C or 176 °F cools down much more slowly after being switched off and still has a temperature of approximately 40 °C or 104 °F after 12 hours. Studies show that customers park their car for more than 16 hours in a row only in 12% of cases.
With each degree of temperature having a significant influence on fuel consumption, this improvement alone provided by encapsulation reduces fuel consumption by up to 0.2% for each extra degree of temperature (in °C).
This method of maintaining temperatures is equally suited for all kinds of vehicles and in all climate zones, although it is somewhat more effective at low temperatures. Highly efficient dampening of heat on the drivetrain also has some positive side effects.
First, measures previously required to dampen noise in the engine compartment are no longer required, since now the source of noise is insulated directly. This saves weight and improves the acoustic behavior of the car. Second, the customer benefits from such innovative insulation of the engine compartment not only through lower fuel consumption, but also through additional comfort, since, apart from acoustic improvements, the insulation also helps to warm up the interior faster in cold weather, as the coolant is also kept warm.

I did a little Googling around and I found some suppliers:
--------------------------------------------------------------------------------------
This one looks like the best option for most areas that can be wrapped and strapped, or screwed thru.
"E.H.P. (Engine Heat Protection) is a space age ceramic material used for insulating components from unwanted heat sources, such as engine pipes, mufflers, cooling systems, and generator compartments, etc."
Engine Heat Protection - Products - Dry Blanket 24" wide by 1" thick $2.49/sq.ft.
Engine Heat Protection - Products - Rollboard 24" wide by 1/8" thick. 200' sq. rolls $1.96/sq.ft.

Engine Heat Protection - Product List
-------------------------------------------------------------------------------------
This one looks like the best option for other areas, but I don't think it works as well as the EHP, and it cost a lot more ($6/sqft).
http://www.carparts.com/HUSH-MAT-HOO...DAMPING SHEETS
* High-temperature butyl polymer adhesive is rated up to 400°F
* Constrained-layer damper incorporates foil film to reflect destructive heat away from your hood and custom paint job

Hush Mat® Hood Heat Dampening Sheets trim easily and conform beautifully to hood surfaces. Includes six 12.1" x 23" sheets.


Has anyone tried this? Any other ideas for material?

I'm too busy now to start, but maybe in Jan. for Feb. I will try it.

[Piwoslaw]

Certain aeromods also help warm-up times: a grille block and belly pan under the engine compartment. If you don't have those, then that's the first step.
Thermal insulation under the hood won't help much at the begining of warm-up, but it will keep the heat in after you stop, giving you a warmer engine if you come back within 1-2 hours.

[RobertSmalls]

Piwoslaw is exactly correct.

Somebody made an engine blanket for his Insight (out of mylar, iirc), but it didn't end up saving appreciable gas. If you're already keeping cold air out of the engine bay, a blanket is not going to make the car warm up much faster.

[MetroMPG]

GDB: do you have a coolant/engine block heater?

Also, FYI, see this threads for in depth discussion of engine insulation, with several examples: http://ecomodder.com/forum/showthrea...tion-6052.html

[Clev]

I thought about another radiator with some kind of phase-change material that could store heat for a few hours. After that, it's just a matter of using thermostats to direct heated coolant there first, and then to the regular radiator once the output from that unit reached engine temp.

I have the flow thought out; I just don't know what kind of material would work well for that (if anything.)

[2speedranchero]

What if you add a small tank with good insulation. I think a 1 gallon tank in line with lower radiator hose covered in rock wool insulation should hold a good deal of heat for several hours. Finding room for it maybe a problem.
Tom