What's Your Engine Temp?

[Jaxonalden]

As I said in my original post "my engine runs cooler than any other vehicle that I drive" and that's all I was getting at. I'm not being obsessed with my coolant temp or watching it like a hawk, I was making an observation that was out of the norm and was just wondering if everyone else had the same temp. Big deal!

BTW, coolant temp is engine temp. If your going to sell the argument that you can use a pyrometer and see greater temps around the engine and then average them for engine temp is ridiculous. The coolant system maintains the engine at a set temperature by the OEM and my point is that Porsche runs their engines cooler than any other manufacture that I know.

An added benny to the 180 degrees means the oil and tranny fluid are also being cooled better.

[Lil bastard]

Hate to disagree, but coolant temp is NOT engine temp - proper combustion could not take place in a 180° environment.

The coolant, flowing through the water jackets does NOTHING to cool either the main, conrod or camshaft bearings - this is carried out by the oil, not the coolant ! The oil sheds this heat through the sump and oil cooler which, in the case of the Boxster, means to the coolant.

In fact, fully 60% of engine cooling is accomplished by the oil - not the coolant !!

The coolant extracts heat from mainly the combustion chamber and the head - cooling the valves in the process.

But, the major components of the engine - the Block, Crank, Pistons, etc. typically run in the 500°-600° range as previously mentioned.

If what you say were true - that coolant temp = engine temp, then no pyrometer reading should exceed 180°- 185° (except maybe the headers/exhaust manifold), which is certainly not the case.

That's not to say the coolant doesn't perform a critical role, it certainly does. But to obsess about it does not accomplish what many mistakenly believe.

[Quickurt]

Actually the size of the water cooling system is calculated to keep the coolant at a usable temperature. It carries off heat from much hotter areas to be dissiminated into the air through the heat exchangers (radiators). The coolant is simply the vehicle used to transfer internal heat to the air. The oil does the same, and in fact in the air cooled engine oil was the only vehicle. Air cooled the cylinder sleeves directly through cast fins, but the heads were cooled by oil, as well as the internals of the crankcase. The air cooled engine also ran much hotter, overall, and was one reason why they had oil seapages. They expanded and contracted more as the temps rose higher and dropped more with the higher operating temperature and oil seal material had to withstand higher operating and aging temps.
As LB points out above, the oil is also cooled via the water in liquid to liquid heat exchangers, so the coolant acts as the vehicle to carry the heat absorbed by the oil out into the air.
I don't know if any are still used, but some industrial and ship engines used steam as the coolant because it allowed higher operating temps than when the coolant could not rise above the boiling point. The reason cooling systems are pressurized is the raise the boiling temp of the coolant (water).
By the way, a simple physics question. If the engine and the coolant are of uniform temperature, how is heat absorbed from the engine, into the coolant, and then released into the air through the radiators, to return to the engine and absorb more heat?

[Quickurt]

By the by, please don't think this is "lecturing."
I can only speak for myself, but I feel it helps everyone understand their cars better, if they understand what everything is really doing.
The main reason European cars have always handled better than American cars is due to a basic philosophical difference between the two industries.
The europeans understand the purpose of the suspension system is to keep the tires in as close to perfect position and loading at all times, to maintain near perfect adhesion between the tires and pavement. Ride comfort is compromised in favor of control.
American manufactures understand the purpose of the suspension system is to give the car as smooth a ride as possible over any type of pavement surface. Control is compromised in favor of ride comfort.
Who's right?
I think the Europeans, Lincoln Town Car owners cheer for the Americans!
The more we all know and understand, the better decisions we should be able to make.
:dance:

[Jaxonalden]

Same song, different verse. For as long as I've been a mechanic the term "engine temperature" refers to the coolant temperature. Because it's gives an overall temp reading of the engine. Read what the coolant temp gauge is called on any car, it doesn't say Coolant Temp it says Eng Temp.

I'm no an idiot to think the engine oil, combustion cylinder temp and exhaust gas (for that matter) is the same temp as the coolant. As I said in my post "The coolant system maintains the engine at a set temperature by the OEM and my point is that Porsche runs their engines cooler than any other manufacture that I know."

Quickurt,

I do not agree with you when you say "The Europeans understand the purpose of the suspension system is to keep the tires in as close to perfect position and loading at all times, to maintain near perfect adhesion between the tires and pavement. Ride comfort is compromised in favor of control.
American manufactures understand the purpose of the suspension system is to give the car as smooth a ride as possible over any type of pavement surface. Control is compromised in favor of ride comfort."

As explained to me by a German in Germany in simple terms as follows;

German cars are built to withstand the Autobahn. The speed, the curves and stopping. Hence the power from Porsche, Audi, BMW and Mercedes. All these cars are built for high speeds, maintaining high speeds and being safe at those speeds.

American car manufactures don't have to build their production cars to those standards. Max speed in this country is 75mph and that's their benchmark and cars are built to that. As a quick example just look at the oil capacity on American cars, 5 quarts. Why do you think our Boxsters have 9 quarts? It's not because the engine has that much more to lube, it's because when running at sustained high speeds for a long time the oil needs to have the ability cool before being sent back around the engine to cool and lube. You think race cars have 5 quarts in their sumps?

So to sum it up, European cars are built stronger because of the Autobahn, American cars are not. I won't get into the fact that there are cry baby Americans that complain about a stiff ride (and won't buy) without understanding the reason for that ride.

[Quickurt]

Jaxonalden,
Okay, settle down.
I don't remember anyone calling anyone anything.
Same song, different verse was a great description for both the coolant discussion and the suspension one. You're right, the autobahn and higher speeds are why the europeans place tire contact and control as a higher priority than cushy ride, while the Americans concentrate on cushy ride because they can.
I described their suspension philosophy and you gave the reasons, but I don't see how we disagreed.
Now, let's have a beer!!

[Lil bastard]

Coolant temp may suffice as a euphemism for engine temp in some quarters, but it's an inaccurate one.

And, some gauges may show the symbol of the engine, but to my experience, most relate to coolant or water such as a water droplet with the symbol for degree (°), or a set of wavy lines simulating water waves with a thermometer sticking in it (such as the Boxster), I've even seen H²O on a gauge of one car I owned.

Neither German or European cars were designed for the Autobahn as your german friend stated, and you need to make a distiction between German and other European manufacturers because the genisis of their way of designing cars is very different.

All European cars are 'better built' in part because of their early history. Europe was slow to adopt Henry Ford's model for mass-producing cars - initially, they took a more craftsman like approach and to some extent this lingers today. But it's a mistake to try and lump them all together.

German cars were NOT designed for the Autobahn as this didn't even exist until shortly before the 2nd World War. They were built to meet the specs of both DIN (Deutsches Institut für Normung), formerly NADI (Normenausschuss der deutschen Industrie), a bureau of Industry Standardization such as our ASE, and later TÜV (Technischer Überwachungs-Verein) standards.

Virtually everything that moves on a German road must have a TÜV certification, including most of the parts, such as tires, wheels, even down to the metal alloy from which the Nuts and Bolts are to be made. In most cases the certificate has to be renewed after two years. A pass of the mandatory roadworthiness and smog test is indicated by tamper-proof decals on the license plate. Most modifications (ie aftermarket parts) also need to be approved. The TÜV safety guidelines are among the strictest in the world, and have largely (though not wholly) been adopted by the EU. Now operating at Autobahn speeds may well be factored into the TÜV standards, but it's meeting the standard and receiving certification, not autobahn driving, that manufacturers design and build to.

But, the basis for design of the Volvo was very different and not to market the cars in germany. It was to survive a long-standing cause of major highway crashes and deaths in Sweden, namely Reindeer ! Collisions with Reindeer was a serious problem causing many deaths. Volvos were built with high, flat, reinforced, front ends to prevent merely knocking the animal off it's long legs which resulted in the carcass sliding over the hood and into the windshield, and subsequently, the driver's/passenger's laps. They were designed to throw the animal over the windshield onto the roof (which is also heavily reinforced) and save the occupants lives. In the late 50's and early 60's, when Mercedes started marketing their cars as 'crashworthy' and safe, Volvo jumped on the bandwagon with a 'safety conscious' car they'd actually been producing from the start.

Other country's cars had similar beginnings, but again, not specifically for operating on the Autobahn.

[Lil bastard]

Actually, the reason European cars have better suspensions than American ones is because they have to. It's a matter of terrain.

The automobile came along very late in europe's history, when towns, villages and roads were already well-established. Because of a lack of heavy machinery a thousand years ago, when roads encountered an obstacle - river, hill, mountain, etc., the road builders went around them, creating roads with lots and lots of curves.

In America, the majority of the roads today were not laid when the car came along, and so (along with an availabilty of heavy machinery) the roads were built specifically to accomodate the automobile and so are generally more straight with milder curves. American cars simply didn't need to handle the way european cars did.