Diabolis

LOL.

TK_BlackBoost - first, you are now bringing an E63 with an M157 TT engine into it. I know nothing about the M157, but the discussion here was about the M156 and M159 engines, not the M157. Second, your statement that reads "Instrument Cluster: Coolant 94 Celsius; OBD read: Coolant 108 Celsius" which you are presenting as evidence and basing your conclusions on is obviously very flawed as both the OBD readout and the cluster readout get the data from the same sensor in the car. If you stand on the same scale with two displays and one display shows you weigh 94 kg and the other shows 108 kg, would you really think that you just figured out a way to make yourself 14 kg lighter, or would you perhaps think that the scale may be defective?

Tasos - you may be an OK mechanic, but I am afraid I've lost some respect for you because you either don't understand basic physics, or are involved in the design / production / manufacture / sale of these aftermarket thermostats and have an interest in selling them.

If you tell me that the size of the thermostat opening on the aftermarket thermostats is larger and that they have a higher coolant flow rate than the OEM thermostats when they are fully open, I'll accept that despite the fact that no M165 or 159 engine has *EVER* been shown to suffer from coolant overheating unless AMG factory mechanics, Mercedes Benz North America and Mercedes-AMG Motorsport Customer Racing are all lying to us (and I have personally seen telemetry data from CRP Racing and DXDT Racing who ran 3 AMG GT3s all over North America at some pretty hot ambient temperatures and none of them have ever shown an issue with coolant temps).

If you continue to insist that a thermostat that simply opens at a lower temperature vs. one that opens at a higher temperature is somehow going to magically lower the engine temperature when the coolant temperature is higher than the temperatures at which both of those thermostats fully open and they have the same size opening and thus flow rate, then I am afraid it only proves why you are a mechanic and I am an engineer seeing as you felt it appropriate to point that out in your video reply. And, Canada is not as cold as you think it is... well, maybe in the winter, but not in the summer, and furthermore, if you spend a weekend south of the border at COTA, VIR or Sebring in middle of summer, I can guarantee you that it is not any cooler than it would be anywhere in Greece.

Cheers.

Diabolis

Possibly, even likely yes. The problem is that a thermostat that simply opens at a lower temperature will not drop the coolant temperature at all. You do know what the thermostat does, right? It doesn't regulate the engine temperature - it only allows the engine to warm up quicker while it is closed.

Jasonoff

The sensor in block, which is used for engine management, is not what's displayed in the dash. See my edited post (https://mbworld.org/forums/c63-amg-w...ml#post8347320) with some datalogging. The dash temp would display in the 92-94°C range.

skratch77

Not that it implies directly but my tuning on my w205 runs the pumps constant and it takes me about 25 min to get out of the blue. So there is definitely a difference. I even got an engine to cold code once lol.

Diabolis

You are now going to make me reach out to Mercedes-AMG Germany to find out what sensors are used for the dash temp and OBD temp readouts.

At any rate - WHATEVER sensor(s) the telemetry data is being pulled from on the AMG GT3 race cars, they do not indicate that the cars are ever running hot. Neither does your data except for when you had a portion of your radiator blocked.
They all run in the 105-110 C range regardless of ambient temperatures.

Diabolis

That is my point exactly Sir. It simply takes your engine a longer time to reach operating temperature, but it doesn't lower said operating temperature once the engine is fully warmed up.

Jasonoff

No clue where the dash gets the temp from but if you or anyone else here can find out, it would be good to know. I assume it's somewhere down lower closer to the pump to read what the inlet temps are.

The OBDII temp comes from the sensor in the block just above where the thermostat housing is.

skratch77

The engine being warmed up is controled by the thermostat. My car runs 10to15c cooler than stock file

deadlyvt

I don’t know why it’s hard to understand, the thermostat simply changes the temperature at which the coolant begins to flow to the radiator and begin cooling before entering the engine. It doesn’t cool or affect the cooling in any way. The only way it can is if it was to construct flow at a pretty meaningful rate. Having it open at 10,15,55 or all the time doesn’t in any way affect the overall cooling of the engine it only allows the coolant to begin cooling in the radiator sooner in relation to engine operating temperature.

Jasonoff

That's the whole point of this product. The t-stat, while completely open, still restricts quite a bit of flow. It was stated in one of the videos that this product increase flow by around 20% which is significant and explains the data provided in a previous post.

TK_BlackBoost

Hello there,

the numbers that I have provided are logs, logs that have been recorded at the same day on the same car with the same driver. You said that you are the engineer and tasos just an mechanic and wont be more than that. yet you dont know that the display number on your dash is not the actual temperature on your engine? I dont know why you have to get personal here. Be happy that you are engineer, people are happy that tasos is one of the most understanding person on engines, who did as much as no one else for the AMG community. Dont get personal here please and dont think that a degree makes you a better person and or a more intelligent. I was working for the development of Merc cars in Sindelfingen, am I now a better person? No im not.

Some more things here upcoming:

- 1000W plug and play fan
- controller to controll the fan, coolant pumps at 100% efficience (can be done by ECU but then the fan is always operating at 100% some ppl dont like to have it always noisy.)

Diabolis

Amen.

In that case they should market it as a higher flow rate thermostat instead of arguing that a lower temperature thermostat will magically decrease engine temperatures. Furthermore, if the coolant flow rate is insufficient to properly cool the M156/159 engines, removing the thermostat completely and simply blocking off the coolant recirculation port would work even better, which IIRC is what Barry stated earlier in the thread.

And, @SRG_C63 makes an excellent point in post #24 --- you actually need the engine to operate at a specific temperature in order to optimize combustion and thus power. Overcooling the engine can be just as detrimental as overheating it.

As I said earlier, this is a solution to a problem that doesn't exist. Period.

Diabolis

Well, perhaps you should tell him that. He is the one that said "this guy doesn't know what he is talking about... he is not a mechanic" in his video reply.

As for the numbers on the display, I admit that I don't know which specific sensor they are being pulled from. The discrepancy here is that in one case you are showing a 14 degree difference between the OBD and dash readings (when it suits you to show said difference), but in the other there is only a 1 degree difference between the two. If they are readings from different sensors and the coolant temperature is 14 degrees cooler at the first sensor in the first measurement but only 1 degree cooler in the second, how do you explain the discrepancy? Do you see the problem here?

Jasonoff

It does reduce operating temps AT the block (OBDII reading) because of the extra flow through the radiator. From what I have read, the M156 likes to operate in the 102-108°C range. It appears in a hot climate like the UAE, a "fully open" t-stat is restricting too much flow to the rad causing those temps to rise so they developed a solution.

Isn't that exactly what this product does?

It is a problem in their environment though. That's why this product was developed and from the looks of it, thoroughly tested before releasing to "their" market as well.

In stock form with non extreme ambient temps I doubt anyone would have coolant temp issues. The car was designed for it. I highly doubt it was designed to run in 45°C temps all day long.

I myself caused coolant temp issues by adding a larger front mount oil cooler to solve oil temp issues but in turn caused the coolant temp problems. What I did (blocking some air flow to the rad so the oil cooler had priority) is probably very similar to increasing the outside ambient air to extreme temps.

TK_BlackBoost

Hello there,

the hole point here is to show that the actual number on the display has nothing to do with the number on the engine, for us the number on the engine matters and not a programmed value output on the display which OEM did. This is why when you monitor your display you are seing basically nothing because you dont know the actual value of temperatures.

Jasonoff

Do you know where they get it from? Is it just a programmed value based on input from multiple sensors?

TK_BlackBoost

Hello there,

I will look into the functionrahmen to see what is mentioned word by word, functionrahmen always very difficult to read. :-) ill do my best.

Tasosmos2

Let's start:
1st
Instrument Cluster: Coolant 94 Celsius
XENTRY read: Coolant 108 Celsius

2nd
Yes i'm just a mechanic

3rd
I don't care if you respect me or not

4th
The oem thermostat or an aftermarket thermostat have flow restriction naturally
because of the design of the thermostat

5th
That's the problem with the engineers, they think that all it's theory

6th
I'm just an employee, i don't care if the company sell 1 thermostat or 1,000

7th
If you tell me that the size of the thermostat opening on the aftermarket thermostats is larger and that they have a higher coolant flow rate than the OEM thermostats when they are fully open
This is exactly what i'm saying but you are engineer

8th
I'll accept that despite the fact that no M165 or 159 engine has *EVER* been shown to suffer from coolant overheating
I can found 20 people easily, in fact i have right now in the garage a bone stock C63 with 100k km and in a race track the coolant temp reaching at 140 degrees celsius

9th
3 AMG GT3s all over North America at some pretty hot ambient temperatures and none of them have ever shown an issue with coolant temps
You compare GT3s that have racing setup with what? with an SLS from the production line or with C63?
The 3 AMG GT3s when they racing have 100k km the engines? and do they use coolant or distilled water?

10th
If you continue to insist that a thermostat that simply opens at a lower temperature vs. one that opens at a higher temperature is somehow going to magically lower the engine temperature when the coolant temperature is higher than the temperatures at which both of those thermostats fully open and they have the same size opening and thus flow rate, then I am afraid it only proves why you are a mechanic and I am an engineer seeing as you felt it appropriate to point that out in your video reply.
I agree with that and i'm very happy to be just a mechanic and not engineer like you.
Obviously you haven't realize that it's a piece of aluminium which closes the bypass path on the timing cover but sorry i forget, you are engineer, try to watch again the pictures

11th
I'm not in Greece i'm in U.A.E the last 10 years, when you feel how it's the 50 degrees Celsius then come and talk to me for cooling system.

Thank you for wasting my time

Phil1305

ok, so going back to look at this and my dumbass over looking it and referencing a basic chevy small block while taking out the thermostat.

This is essentially doing just that as in removing the thermostat. It only blocks off the front cover from recirculating coolant back into the engine which tasos did state but my dumbass didn't pay attention to. So this essentially deletes the temperature regulation the thermostat provides and is always open, again which is stated previously.

The problem with all the arguing and arrogance above is that proper logging with a stock thermostat a 180 t stat and the black boost t Stat is needed to gather data to see where the engine temperature stabilizes at. I do agree that there is no real issue with the m156 cooling system for the most part in stock form. Engines do have a certain temp at which is optimum for combustion efficiency to take place, but that's at a trade off for emissions regulation and comfort for the cabin as in heat for the winter time. Most cars are ran to around 200 degrees to mainly help combat tail pipe emissions. This also why most "performance " thermostats are around 160-180 as your engine would probably run a bit better there and make a little more power from running a tad cooler.

I would still like to see datalogs for the three given t stats with equal variables to see how the cooling system performs and where the Temps stabilize at. Ie a 30 min cruise with logs between the 3 and a 30 min idle between the 3 at the same Ambient Temperatures. Now the idle test would be a moot point as the rad fan kicking on at its programmed temp would alter the readings, but say kick on factory for stock t Stat and 180 for 180 t Stat and always on for the blackboost t Stat for a more accurate test.

Obviously the blackboost is developed for a very hot climate but id still like to see some tests done and what the data shows. Just my thoughts and not asking blackboost to do these tests.

Diabolis

In which case it should also reduce the coolant temperature at the other sensor used to indicate the same on the dash, no?

By the look of things, yes. However, their original post did not state that the flow rate with the OEM thermostat is reduced even when it is fully open when compared to their bypass, and I have to admit that I did not watch their two promotional videos. They simply stated that the OEM thermostat doesn't fully open before 100C / 212F, which theirs "fixes".

Well, let's play this out to its logical conclusion then. If the ambient air is so hot in their environment that they need the extra 5% flow through the radiator, then the considerably worse oil cooling issue is going to rear its ugly head *WAY BEFORE* anything coolant related ever affects the performance of the car. On the other hand, if you completely remove the oil cooler in front of the rad (like the 44O kit does), the coolant temperature - including the one displayed on the dash from the second mystery sensor - also reads at least 10C lower, and this I can attest to personally as installing the 44O kit on mine resulted in coolant temps in the 93-96C range during 45-minute track sessions in the middle of July and August at ~40C ambient, and furthermore as evidenced by the fact that AMG developed the 44O oil cooling kit for the C63 F1 medical car when they were driving it in Bahrain and Abu Dhabi but didn't think it worthwhile to do anything about the coolant temps (which we both agree are lower after removal of the oil cooler in front of the rad). So again - what problem does this solve on the M156 and M159 equipped cars?

If you modify an M156 engine (they mention supercharging), then sure - although in that case on a W204 you'll again have to deal with the overheating oil *way before* you'll need to do anything about the coolant temperature. I have no problem with them making "you need lower coolant temperature" claims to the M157 5.5L TT crowd (which is what their temperature data is from), the M178 4L TT cars or for that matter anyone with a B180 because I know nothing about those engines. However, when it comes to any car ever made with an M156 or an M159 engine, to the best of my knowledge - and I am basing this on statistically significant amounts of first-hand data as well as information directly provided by various Mercedes-AMG divisions - overheating because of high coolant temperatures has never been an issue under any circumstances in any environment. That much I do know.

Diabolis

Likewise my friend. If you had said "it's just a thermostat bypass", all of this could have been easily avoided.

And, just because I can find 20 people that think lizard people live among us, that doesn't make it so. You have a bone stock C63 with 100k km and in a race track the coolant temp reaching at 140 degrees celsius - but you don't have any issues with overheating oil? Really?

Jasonoff

From the sounds of it, it's some sort of calculated value. How it's calculated will hopefully be revealed here at some point.

After spending most of last season sorting out cooling issues, first oil, then coolant. I have observed there's absolutely no direct relationship between what's displayed on the dash and what's read at the sensor OBDII has access to. I have seen the dash display 94 and CTS 102, then the dash display 92 but the CTS 105 which didn't make much sense to me.

hachiroku

my 2 cents on this topic is...

a reduction of flow restriction by bypassing of the thermostat will assist in keeping temps lower to a point, but if you've already reached the maximum efficiency of that heat exchanger, you've reached the maximum and yes you'll need a larger heat exchanger or improved flow across that heat exchanger. while I do see the merit in a product for the most extreme of temperatures as a workaround to redesign of the entire cooling system, my racing experience background understands there is no replacement for a properly designed high efficiency cooling system like a thicker radiator or in the case of all of my race cars and friends race cars, a dual pass extra thick aluminum custom radiator. one other thing, as seen with turbocharged vehicles with large aluminum radiators that still over heat on the race track, this is generally caused by a reduction of airflow and essentially things like a larger air to air intercooler slowing and heating the air before it touches the engine radiator which at this point does put the radiator in a less than ideal situation to actually provide any cooling. in situations like this, a redesign of the airflow and placement of each individual heat exchanger is the ultimate solution here. we all already know the heat exchanger placement and design for the W204 is lacking and subpar and would best benefit from a redesign, i.e. like the 44o or black series configuration.

as Phil stated, the only way we'll know for sure is the see the datalogs for varying situations. daily driving, race situations, and supercharged situations. do we need more parts and development for the M156/M159, yes, but parts like these are used for very specific use cases of which the majority of us will not have a need for which was stated. with that in mind, I do personally know racers that would run this type of product. across my racing life, about 10% of racers i've encountered would go this route before a 2nd or 3rd cooling system full redesign to rule out hot run conditions. i am not one of them, but as mentioned, i've encountered about 10% of racers that would use a product like this until they've fully redesigned their cooling system from the ground up.

SRG_C63

I have also thought about this.

hachiroku

oil temps have a direct correlation with coolant temps. if coolant temps rise so will oil temps.