Quote: Originally Posted by forcefedjunkie
I've had an EGT gauge mounted about 2" from port 1 of the cylinder head for a week now. These actual readings compare pretty well to those calculated by the PCM. I have a 50 trim turbo which may or my not effect the PCM determined EGT temperature.
Autometer EGT reading Interceptor EGT reading from PCM
750 (idle) deg F 950 deg F
1050 1125
1200 1275
1300 1400
1400 1500
1550 1650 (WOT)
Once the actual got over 1000 deg F the difference between the two was a fairly constant 100 deg. I don't know exactly where the PCM is determining the temperature, perhaps at the cylinder exit of combustion chamber. I'll be interested to see if the stock turbo readings are closer.
Todd
According to the SRT Engineers, the PCM does not calculate EGT:
http://www.chargerforums.com/forums/...95&postcount=2
or for convenience:
Calculated EGT's.
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1. How exactly does the SRT-4 PCM calculate EGT's? (what are the input parameters).
2. What does the SRT-4 PCM use the calculated EGT's for? (is it just a byproduct calculation or does it actually influence the PCM to change other variables like boost, ignition advance timing, injector pulse widths, fuel trims).
Obviously, noone in the right mind would tune a car based solely on calculated EGT's. But those of us with OBD-II scan gauges are aware of the calculated EGT readout and would like to know more about it. Unfortunately, the PCM is a black box to everyone outside of DCX, hence this question to the SRT engineers.
We do not calculate EGT as part of the ECM. The EGT's are measured on the dyno and car and we do not cross selected limits depending on the Components in the exhaust flow such as the exhaust valve and the turbine wheel. the leaner , the hotter the EGT's, higher the power until parts break.
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Last edited by Team SRT : 07-18-2007 at 05:14 PM.
To be honest, I was quite suprised at this. So who is right? The SRT Engineers or you? It's not a huge deal. I just would like to know more about how and where the calculated EGT's are derived. Thanks!
