BMW: heat is goot!

RACER X · 10-19-2009, 01:08 PM

According to BMW's research, starting and running a vehicle's engine while cold is not only tough on internal components, it's also tough on your wallet. BMW says that during the first 20 minutes of driving, a cold-started engine requires 10% more fuel to operate than a warm-started engine because of higher internal friction and oil viscosity. Further, the automaker claims that every single degree Celsius that the engine is warmed prior to being started results in a 0.2% fuel economy savings (again, during the first 20 minutes of driving).

Why is this? Two-thirds of the energy from fuel becomes heat, and it takes a lot of heat to get a vehicle up to proper operating temperature. In fact, BMW says that the amount of energy required to warm up a cold engine to normal temperature is equivalent to 8kW - that's about one-third of the daily energy required by a two-person household. BMW's solution? Eliminate cold starts.

Using thermal padding around the engine compartment, a lift-up hatch that seals in heat above the engine cover, and air flaps behind the front grille that open when driving and shut closed when the vehicle is turned off, BMW says it can retain a large amount of the heat the engine has generated while running, keeping the engine warm for the next time it is started. BMW claims that overheating is not an issue with the extra insulation - in fact, components that once needed extra cooling are now separated by the engine's heat by the insulation, staying at optimal temperature in the process.

How effective is the technology? BMW's tests show that an engine running at 176 degrees Fahrenheit will retain a temperature of roughly 104 degrees after 12 hours of inactivity, versus a complete return to ambient temperature without insulation. Further studies show that BMW drivers rarely park their cars for more than 16 hours at a time, leading engineers to believe that the technology could be highly useful in practical, real-world applications.

BMW says that this technology is close to being production-ready, needing only minor tweaking to provide greater engine access for mechanics while vehicles are being serviced.

Source: BMW

tached1000rr · 10-19-2009, 01:14 PM

BMW and their gadgetry, wonder how much it would add to the sticker price??

Just give me a 4 barrel carb, a solid lift cam, and some manual roll up windows!

CasterTroy · 10-19-2009, 01:20 PM

Quote:

Originally Posted by tached1000rr

BMW and their gadgetry, wonder how much it would add to the sticker price??

Just give me a 4 barrel carb, a solid lift cam, and some manual roll up windows!

But how would the gov track you and know your speed/location?

tached1000rr · 10-19-2009, 11:36 PM

Quote:

Originally Posted by CasterTroy

But how would the gov track you and know your speed/location?

The is a bear in the air!

Homeslice · 10-19-2009, 04:07 PM

Great, make the underhood area even more boring than it already is.

Rider · 10-19-2009, 04:16 PM

Makes complete sense. Not sure why anyone hasn't been doing something like this already. Everyone has known for years that a warm engine is more efficient and less damaging than a cold engine. Sure it's boring to look at but do you really pop the hood and admire your (modern) engine anyway? I mean, engines of today don't have the sex appeal of a late 60's V8. Exotic cars of course being exempt from this statement.

101lifts2 · 10-19-2009, 11:16 PM

Well, BMW is part true. The main point isn't to get the engine up to operating temperature, the point is to get to the cat lit off as fast as possible. This is accomplished by timing retardation and a low A/F ratio.

Now, holding in engine heat will allow less fuel over a drive cycle which means better economy, lower toxic emissions as well as lower C02.

I'm all for it. Good job BMW.

Homeslice · 10-19-2009, 11:20 PM

Quote:

Originally Posted by Rider

Makes complete sense. Not sure why anyone hasn't been doing something like this already. Everyone has known for years that a warm engine is more efficient and less damaging than a cold engine. Sure it's boring to look at but do you really pop the hood and admire your (modern) engine anyway? I mean, engines of today don't have the sex appeal of a late 60's V8. Exotic cars of course being exempt from this statement.

IMO the only thing sexy about a 60's V8 was if the air cleaner was chrome......Everything else was usually boring-looking unless you spent a lot of time & money prettying it up. The hoses and wires back then had no organization whatsoever (because the excess room under the hood made the manufacturers lazy), and the manifolds were blocky and not shaped as exotically as today's are.

pauldun170 · 10-19-2009, 11:40 PM

translation: Oil changes will now require 3 hours of removing panels. Spark plug changes will require 3 days. Changing an accessory belt will require dismantling the car down.
Water pump change will require complete replacement of car

goof2 · 10-20-2009, 12:54 AM

I agree. I don't care about admiring an engine, but I do care about maintaining it. I keep vehicles for a long time, a lot longer than BMW's "included" maintenance period. I'm not paying a dealer $300 in labor to remove, and later replace, a ton of crap around the engine before they even start working on the car.

As for the earlier question about why no one has done this before I can think of a few reasons. A warm engine is best, but once it gets warm a lot of effort goes in to keeping it from getting hot.

One thing that helps is airflow around the engine. Wrapping the engine in heat blankets kind of kills that option. Now you need a larger radiator (weight), more coolant (weight), and a larger cooling fan that needs to run more (more draw on the alternator). Lugging around that extra weight, plus the additional weight of the system, as well as heavier draw from the alternator all contribute to more fuel consumption.

That extra fuel consumption is not particularly significant, but it is always happening. The fuel savings of this system are not particularly significant either, it only occurs for the first 20 minutes, and its effect is diminishing over that time. This system may result in a net benefit, but it will be smaller than even the minuscule numbers claimed in the article. I would trade that benefit for slightly easier maintenance in a heartbeat.

10-19-2009, 01:08 PM	#1
RACER X AMA Supersport Join Date: Nov 2008 Location: Richmond, Tx Moto: '10 Tuono Factory Posts: 4,569	BMW: heat is goot! According to BMW's research, starting and running a vehicle's engine while cold is not only tough on internal components, it's also tough on your wallet. BMW says that during the first 20 minutes of driving, a cold-started engine requires 10% more fuel to operate than a warm-started engine because of higher internal friction and oil viscosity. Further, the automaker claims that every single degree Celsius that the engine is warmed prior to being started results in a 0.2% fuel economy savings (again, during the first 20 minutes of driving). Why is this? Two-thirds of the energy from fuel becomes heat, and it takes a lot of heat to get a vehicle up to proper operating temperature. In fact, BMW says that the amount of energy required to warm up a cold engine to normal temperature is equivalent to 8kW - that's about one-third of the daily energy required by a two-person household. BMW's solution? Eliminate cold starts. Using thermal padding around the engine compartment, a lift-up hatch that seals in heat above the engine cover, and air flaps behind the front grille that open when driving and shut closed when the vehicle is turned off, BMW says it can retain a large amount of the heat the engine has generated while running, keeping the engine warm for the next time it is started. BMW claims that overheating is not an issue with the extra insulation - in fact, components that once needed extra cooling are now separated by the engine's heat by the insulation, staying at optimal temperature in the process. How effective is the technology? BMW's tests show that an engine running at 176 degrees Fahrenheit will retain a temperature of roughly 104 degrees after 12 hours of inactivity, versus a complete return to ambient temperature without insulation. Further studies show that BMW drivers rarely park their cars for more than 16 hours at a time, leading engineers to believe that the technology could be highly useful in practical, real-world applications. BMW says that this technology is close to being production-ready, needing only minor tweaking to provide greater engine access for mechanics while vehicles are being serviced. Source: BMW __________________ ΜΟΛΩΝ ΛΑΒΕ 2014 GROM! 181cc of FURY 2010 Aprilia Tuono Factory - SOLD 2009 SFV Gladius - SOLD 2008 Hayabusa - SOLD.

10-19-2009, 11:16 PM	#7
101lifts2 WSB Champion Join Date: Nov 2008 Location: Anaheim, CA Moto: 2009 Kawi ZX6R Posts: 5,570	Well, BMW is part true. The main point isn't to get the engine up to operating temperature, the point is to get to the cat lit off as fast as possible. This is accomplished by timing retardation and a low A/F ratio. Now, holding in engine heat will allow less fuel over a drive cycle which means better economy, lower toxic emissions as well as lower C02. I'm all for it. Good job BMW. __________________ Train Hard Ron Paul - 2012 Mark of Excellence GM Last edited by 101lifts2; 10-19-2009 at 11:26 PM..

10-19-2009, 01:14 PM	#2
tached1000rr WERA White Plate Join Date: Dec 2008 Location: NC Moto: 2009 GSXR 1300 Posts: 2,448	BMW and their gadgetry, wonder how much it would add to the sticker price?? Just give me a 4 barrel carb, a solid lift cam, and some manual roll up windows!

10-19-2009, 04:07 PM	#5
Homeslice Elitist Join Date: Nov 2008 Location: SF Bay Area Moto: Gix 750 Posts: 11,351	Great, make the underhood area even more boring than it already is.

10-19-2009, 04:16 PM	#6
Rider Moto GP Star Join Date: Feb 2008 Posts: 12,156	Makes complete sense. Not sure why anyone hasn't been doing something like this already. Everyone has known for years that a warm engine is more efficient and less damaging than a cold engine. Sure it's boring to look at but do you really pop the hood and admire your (modern) engine anyway? I mean, engines of today don't have the sex appeal of a late 60's V8. Exotic cars of course being exempt from this statement.

10-20-2009, 12:54 AM	#10
goof2 AMA Supersport Join Date: Feb 2009 Posts: 4,756	I agree. I don't care about admiring an engine, but I do care about maintaining it. I keep vehicles for a long time, a lot longer than BMW's "included" maintenance period. I'm not paying a dealer $300 in labor to remove, and later replace, a ton of crap around the engine before they even start working on the car. As for the earlier question about why no one has done this before I can think of a few reasons. A warm engine is best, but once it gets warm a lot of effort goes in to keeping it from getting hot. One thing that helps is airflow around the engine. Wrapping the engine in heat blankets kind of kills that option. Now you need a larger radiator (weight), more coolant (weight), and a larger cooling fan that needs to run more (more draw on the alternator). Lugging around that extra weight, plus the additional weight of the system, as well as heavier draw from the alternator all contribute to more fuel consumption. That extra fuel consumption is not particularly significant, but it is always happening. The fuel savings of this system are not particularly significant either, it only occurs for the first 20 minutes, and its effect is diminishing over that time. This system may result in a net benefit, but it will be smaller than even the minuscule numbers claimed in the article. I would trade that benefit for slightly easier maintenance in a heartbeat.