AEM EMS and Temperature gauge
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Joined: May 2001
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From: Indian Land SC
Update - I have done some serious research.
1. The ECM output to the gauge responds instantly to changes in the ECT sensor signal.
2. The gauge has a delay built-in, but it's not as bad as I remember. It takes 10-12 seconds per segment, for the gauge to update.
3. The ECM output to the gauge is not linear, but jumps in increments that sometimes, but not always, correspond to the gauge display.
4. On top of that, the OBDII temperature jumps in increments too, and it sometimes, but not always, corresponds to the gauge display. Pretty goofy if you ask me.
5. The gauge has 6 active segments. The first segment (not active) is ON all the time, then there are 5 orange segments and one red segment.
6. The display is designed to always indicate the "3 bar" display unless there is something really wrong. It has an "active" range of 160
1. The ECM output to the gauge responds instantly to changes in the ECT sensor signal.
2. The gauge has a delay built-in, but it's not as bad as I remember. It takes 10-12 seconds per segment, for the gauge to update.
3. The ECM output to the gauge is not linear, but jumps in increments that sometimes, but not always, correspond to the gauge display.
4. On top of that, the OBDII temperature jumps in increments too, and it sometimes, but not always, corresponds to the gauge display. Pretty goofy if you ask me.
5. The gauge has 6 active segments. The first segment (not active) is ON all the time, then there are 5 orange segments and one red segment.
6. The display is designed to always indicate the "3 bar" display unless there is something really wrong. It has an "active" range of 160
Thread Starter
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Joined: Oct 2000
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From: Sydney
It looks like the gauge is pretty dumbed-down to keep people happy. Personally I'd rather have a better indication of the actual temperature and would prefer more resolution in the mid range.
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Joined: May 2001
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From: Indian Land SC
OK, I've gotten some feedback in the post and via PM's, but I need specific suggestions.
Exactly what temperature range do you want to display on the stock gauge?
Right now it goes from 131
Exactly what temperature range do you want to display on the stock gauge?
Right now it goes from 131
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Joined: Jan 2002
Posts: 15,835
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From: Vegas Baby, Vegas
Well, here's a datapoint for you. I've seen 4 bars on the track out in the SoCal high desert in mid-summer. We're talking air temps in the 110s, track temps in the 160+ range. Made me back off right away, take a cooldown lap and bring it into the pits.
Contributing factor: A Coastal Metals grill on the front of the radiator opening.
Solution: Remove grill for track days.
Would I like a more accurate gauge, damn right I would. It's obvious Honda, and other manufacturers, "dumb down" their gauges so Mr and Mrs Public doesn't lose that warm fuzzy feeling while pounding down the interstate in mid-summer with AC and DVD blasting away.
But here's something you might not be taking into account. There are lots of people out there with cooling mods, i.e., the Spoon, Speed or Mugen packages which often include a higher pressure radiator cap as part of the mix. Given that, would a high temp of 235 be as much cause for concern when running a 1.35 bar radiator cap as running a factory 1.1 cap?
In any case, I think this is a worthwhile project. I think for under $100 you'll have a market. You know where to reach me
J.P.
Contributing factor: A Coastal Metals grill on the front of the radiator opening.
Solution: Remove grill for track days.
Would I like a more accurate gauge, damn right I would. It's obvious Honda, and other manufacturers, "dumb down" their gauges so Mr and Mrs Public doesn't lose that warm fuzzy feeling while pounding down the interstate in mid-summer with AC and DVD blasting away.
But here's something you might not be taking into account. There are lots of people out there with cooling mods, i.e., the Spoon, Speed or Mugen packages which often include a higher pressure radiator cap as part of the mix. Given that, would a high temp of 235 be as much cause for concern when running a 1.35 bar radiator cap as running a factory 1.1 cap?
In any case, I think this is a worthwhile project. I think for under $100 you'll have a market. You know where to reach me
J.P.
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From: Vegas Baby, Vegas
It also depends on what the "normal" temp is for the car. I had a Pontiac 20 years ago that liked to run a 220 normally, maybe 190 on the highway.
I don't know if 230-240 is an acceptable high number. When I hit 4 bars, I didn't shut the car off in a panic, coolant wasn't discharging from the overflow or the cap so there was no indication other than that one lonely extra bar on the gauge that something wasn't normal. I guess you need to know the answer to where the danger zone really is to get the new calibration right.
RE: the boilover temps with regards to caps, I don't know. The actual boiling point has a lot to do with the coolant mix but not sure where the caps "blow."
I don't know if 230-240 is an acceptable high number. When I hit 4 bars, I didn't shut the car off in a panic, coolant wasn't discharging from the overflow or the cap so there was no indication other than that one lonely extra bar on the gauge that something wasn't normal. I guess you need to know the answer to where the danger zone really is to get the new calibration right.
RE: the boilover temps with regards to caps, I don't know. The actual boiling point has a lot to do with the coolant mix but not sure where the caps "blow."
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Joined: Feb 2002
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From: PDX
I've not bothered to read this entire thread (sorry), but some of you might be interested in my efforts to control my operating temperatures on my turbo'd, EMS-equipped, S2K. The discussion is located at:
https://www.s2ki.com/forums/index.ph...f=133&t=232925
My experience has been that four bars is pretty rare, even those of us who've gone FI and track their cars, unless there's a serious problem. That said, it's also not clear that running ECTs of 220 degrees F. or slightly more is problematic, per se. My sense is that oil temperatures matter more than coolant temps, provided that your coolant doesn't get so hot that it boils. That, in turn, is dictated by your radiator cap.
As an aside, (i) the recommended operating range for the F20c, per the Helm's manual, is 176 degrees F. to 212 degrees F., (ii) I, personally, would not drive my car into VTEC until my oil was sufficiently warm (160 degrees or more), regardless of my ECT value, and (iii) if you're tracking your car and your FI, you should seriously consider an oil cooler of some sort, as I can almost guaranty you that your oil temps are hitting 285 degrees F. or more, which I do think is problematic, regardless of your ECTs.
In any case, if I were designing the system, I'd go with Modify's settings, as I think they span a realistic operating range:
2 bars - 160
https://www.s2ki.com/forums/index.ph...f=133&t=232925
My experience has been that four bars is pretty rare, even those of us who've gone FI and track their cars, unless there's a serious problem. That said, it's also not clear that running ECTs of 220 degrees F. or slightly more is problematic, per se. My sense is that oil temperatures matter more than coolant temps, provided that your coolant doesn't get so hot that it boils. That, in turn, is dictated by your radiator cap.
As an aside, (i) the recommended operating range for the F20c, per the Helm's manual, is 176 degrees F. to 212 degrees F., (ii) I, personally, would not drive my car into VTEC until my oil was sufficiently warm (160 degrees or more), regardless of my ECT value, and (iii) if you're tracking your car and your FI, you should seriously consider an oil cooler of some sort, as I can almost guaranty you that your oil temps are hitting 285 degrees F. or more, which I do think is problematic, regardless of your ECTs.
In any case, if I were designing the system, I'd go with Modify's settings, as I think they span a realistic operating range:
2 bars - 160
Joined: Mar 2002
Posts: 588
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From: Bellingham
It would be nice if the third bar indicated normal operating temps when using a Spoon/Mugen T-stat as well as a stock T-stat. I think it would also be nice if after four bars, all the bars lit up for a better indication of trouble.
Example:
2 bars - 160
3 bars - 165
4 bars - 195
5 bars - 200
6 bars - 200
7 bars - 200
This gives you limited but critical information.
And yes, I would be interested in purchasing this as well. I assume that this would need to be spliced into the existing wire harness?
Example:
2 bars - 160
3 bars - 165
4 bars - 195
5 bars - 200
6 bars - 200
7 bars - 200
This gives you limited but critical information.
And yes, I would be interested in purchasing this as well. I assume that this would need to be spliced into the existing wire harness?
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Joined: Feb 2002
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From: PDX
Given that the Helms manual indicates that a "normal" operating temperature range is 176-212 degrees F. and given that 200 degrees is well within any definition of a "safe" range no matter what radiator cap you're using, I don't see much merit in having all the bars light up at 200 degrees....