AEM EMS and Temperature gauge
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Joined: Feb 2002
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From: PDX
LudeDude:
Your point's fair. I personally just would feel (and did feel a month ago at PIR) highly uncomfortable running my car to 235 degrees, regardless of how the stock gauge is setup. So, for me, that's a "stop now, you idiot" threshold, and I prefer the finer (and more predictable resolution) of 15 degree increments. But I certainly won't get fussed about a higher threshold.
Modifry:
1. For information on the EMS resistances for the ECT sensor, PM GilbertG. He'll know. He developed the calibrations I'm now using for this sensor. The AEM-provided ECT calibrations are wrong. I use the stock ECT sensor and the datastream is read and interpretted by the EMS.
2. I prefer the simplest approach possible, so (to my mind) the ideal solution is to change the calibrations that drive the illumination of the bars in the current gauge. I don't need (or want) any flashing lights, separate buzzer, or to change the function of any other instrumentation. Just adds confusion. Keep it as simple as you can.
3. Yes, temps. change quickly, particularly for me, as the thermal load on the radiator is a function of my oil temperature, turbo-center cartridge temperature, and how much heat the engine is generating (which is a function of boost). Even with the huge radiator/oil cooler, I exceed its capacity at full boost in lower gears, but my temps seem to recover pretty quickly.
4. As for the stock and Mugen sensors, here's what I believe to be true:
Operating range (per the Helms Manual): 176-212
Stock thermostat operation: 194 (presumably that's when it's wide open, but I don't know this for certain)
Mugen thermostat operation: 154 (cracking temp); 181 (wide open)
Stock fan activation: 199 (I don't know if it also turns off at that temp. or at a lower one)
Mugen fan activation: 176 (same deal -- this might also be the temp when it turns off, but I'm not sure)
5. As for your "quick test", remember that the fan switch is located in the lower -- return -- line from the radiator. Thus, the absence of air flowing through the radiator -- which happened when you parked your car -- resulted in the coolant growing suddenly hotter. I don't think the "load" of the radiator had anything to do with your sudden rise in ECTs. That happened, I'd guess, because the water pump is operating more slowly at idle and you generated a thermal load prior to parking the car that was still being absorbed by the block while, at the same time, you reduced the thermal absorption capacity of the cooling system (by slowing the airflow through the radiator, thus sending hotter coolant back into the block and by reducing the rate at which coolant flows through the engine).
6. Personally, I aimed for a normal operating range of 180 degrees to 200 degrees (ECT) and 210 degrees to 220 degrees (oil), although I'm not unhappy with the range I'm getting (185 to 230 degrees).
Your point's fair. I personally just would feel (and did feel a month ago at PIR) highly uncomfortable running my car to 235 degrees, regardless of how the stock gauge is setup. So, for me, that's a "stop now, you idiot" threshold, and I prefer the finer (and more predictable resolution) of 15 degree increments. But I certainly won't get fussed about a higher threshold.
Modifry:
1. For information on the EMS resistances for the ECT sensor, PM GilbertG. He'll know. He developed the calibrations I'm now using for this sensor. The AEM-provided ECT calibrations are wrong. I use the stock ECT sensor and the datastream is read and interpretted by the EMS.
2. I prefer the simplest approach possible, so (to my mind) the ideal solution is to change the calibrations that drive the illumination of the bars in the current gauge. I don't need (or want) any flashing lights, separate buzzer, or to change the function of any other instrumentation. Just adds confusion. Keep it as simple as you can.
3. Yes, temps. change quickly, particularly for me, as the thermal load on the radiator is a function of my oil temperature, turbo-center cartridge temperature, and how much heat the engine is generating (which is a function of boost). Even with the huge radiator/oil cooler, I exceed its capacity at full boost in lower gears, but my temps seem to recover pretty quickly.
4. As for the stock and Mugen sensors, here's what I believe to be true:
Operating range (per the Helms Manual): 176-212
Stock thermostat operation: 194 (presumably that's when it's wide open, but I don't know this for certain)
Mugen thermostat operation: 154 (cracking temp); 181 (wide open)
Stock fan activation: 199 (I don't know if it also turns off at that temp. or at a lower one)
Mugen fan activation: 176 (same deal -- this might also be the temp when it turns off, but I'm not sure)
5. As for your "quick test", remember that the fan switch is located in the lower -- return -- line from the radiator. Thus, the absence of air flowing through the radiator -- which happened when you parked your car -- resulted in the coolant growing suddenly hotter. I don't think the "load" of the radiator had anything to do with your sudden rise in ECTs. That happened, I'd guess, because the water pump is operating more slowly at idle and you generated a thermal load prior to parking the car that was still being absorbed by the block while, at the same time, you reduced the thermal absorption capacity of the cooling system (by slowing the airflow through the radiator, thus sending hotter coolant back into the block and by reducing the rate at which coolant flows through the engine).
6. Personally, I aimed for a normal operating range of 180 degrees to 200 degrees (ECT) and 210 degrees to 220 degrees (oil), although I'm not unhappy with the range I'm getting (185 to 230 degrees).
Thread Starter
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Joined: Oct 2000
Posts: 30,809
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From: Sydney
I love the brainstorm but do hope we don't lose sight of the objectives:
This is what I see as the primaries:
1) Provide stock temperature gauge readout for AEM EMS users
2) Provide a better gauge readout for other ECU (OEM, Mugen, etc) users
Secondary would be:
3) Audible/visual alarm for changes/limits
IMHO anything beyond this adds more complexity and cost and little in actual functionality. But that is just MHO.
This is what I see as the primaries:
1) Provide stock temperature gauge readout for AEM EMS users
2) Provide a better gauge readout for other ECU (OEM, Mugen, etc) users
Secondary would be:
3) Audible/visual alarm for changes/limits
IMHO anything beyond this adds more complexity and cost and little in actual functionality. But that is just MHO.
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Joined: Feb 2002
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From: PDX
Hi Modifry,
Reading between the lines of Aus' post, I guess I've been a bit long-winded...
Sorry. I'll keep this short:
1. Yes, my EMS reads the stock ECT sensor. It then interprets the voltages -- using Gile's ECT calibrations -- to arrive at ECT readings.
2. My apologies. You didn't need a cooling system lecture. I was just responding to what I thought you were saying. I'm now out of explanations. Maybe there's some sort of signal corruption created by the electrical draw of the fan?
3. Simple is better -- I need nothing more than Aus' primary objectives (no warning lights or other things for me).
Thank you for doing this. Every EMS owner has struggled with this issue.
Best,
CBender
Reading between the lines of Aus' post, I guess I've been a bit long-winded...
Sorry. I'll keep this short:1. Yes, my EMS reads the stock ECT sensor. It then interprets the voltages -- using Gile's ECT calibrations -- to arrive at ECT readings.
2. My apologies. You didn't need a cooling system lecture. I was just responding to what I thought you were saying. I'm now out of explanations. Maybe there's some sort of signal corruption created by the electrical draw of the fan?
3. Simple is better -- I need nothing more than Aus' primary objectives (no warning lights or other things for me).
Thank you for doing this. Every EMS owner has struggled with this issue.
Best,
CBender
Thread Starter
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Joined: Oct 2000
Posts: 30,809
Likes: 15
From: Sydney
Originally Posted by cbender,Sep 17 2004, 02:05 AM
Reading between the lines of Aus' post, I guess I've been a bit long-winded... Sorry.
Sorry.The issue I was referring to was all the optional extras and whether they would add cost and time to the project unnecessarily.
I'm not sure if you're familiar with the Hitchhikers Guide to the Galaxy but there is a scene on pre-historic earth where the Golgafrinchans (just bear with me) are attempting to invent the wheel. When Ford Prefect asked them why it is taking so long they respond, "Ok, if you're so smart you tell us what colour it should be!".
In answer to the obvious question I think the Temp Gauge Modifrier should be black!
Joined: Apr 2002
Posts: 4,857
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From: Gold Coast
This sound like the saga of a man without a watch and a man with 2 watches. Neither of them are happy because they don't know the exact time.
If the modifrier unit is cheap and simple I may just join the fun. If it's too much one should just get a external temp gauge. As in my case, if the unit is too much, I will just black out the oem gauge as I aldready have a temp gaguge.
If the modifrier unit is cheap and simple I may just join the fun. If it's too much one should just get a external temp gauge. As in my case, if the unit is too much, I will just black out the oem gauge as I aldready have a temp gaguge.
