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Engine temp vs head temp

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Old Aug 31, 2015 | 01:36 PM
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Default Engine temp vs head temp

What should the degree temperature be between the two
On the 103 motor. I've noticed that the head temperature runs about 100 degrees hotter than the engine temp. The engine temperature is right around 250 in the head temperature runs around 350.
Sounds about right?
 
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Old Aug 31, 2015 | 05:58 PM
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Default Engine temp vs head temp

Mines the same
 
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Old Aug 31, 2015 | 06:13 PM
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Originally Posted by rsking45
What should the degree temperature be between the two
On the 103 motor. I've noticed that the head temperature runs about 100 degrees hotter than the engine temp. The engine temperature is right around 250 in the head temperature runs around 350.
Sounds about right?
How are you measuring these?
 
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Old Aug 31, 2015 | 06:18 PM
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From Jamie at FuelMoto:

There are several temp related channels within the Delphi ECM. The most common channel used is Engine Temperature which is based directly off the 0-5V signal from the ET sensor on the front cylinder head, this channel is reported on the databus as ET. Generally speaking when we speak of engine temp we refer to the data from this channel, we usually consider 240-320F about the normal range relative to conditions, engine mods, and other variables. The second channel is Head Temperature which this is a bit more complex, it is a model the ECM calculates based on the ET sensor, the intake air temp (IAT) and other factors. Head Temp is used within the ECM primarily for Spark Temp correction, for most combination it will run between 260-400F. Note: Heat Temp has been recently added to the PV channel list an is reported as HeadT. The last channel is Coolant Temp which is active on twin cooled and V Rod applications. Hope this info helps...
 
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Old Aug 31, 2015 | 06:35 PM
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Originally Posted by TriGeezer
How are you measuring these?
Using my power vision from Fuel moto
 
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Old Aug 31, 2015 | 06:40 PM
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Originally Posted by J929626
From Jamie at FuelMoto:

There are several temp related channels within the Delphi ECM. The most common channel used is Engine Temperature which is based directly off the 0-5V signal from the ET sensor on the front cylinder head, this channel is reported on the databus as ET. Generally speaking when we speak of engine temp we refer to the data from this channel, we usually consider 240-320F about the normal range relative to conditions, engine mods, and other variables. The second channel is Head Temperature which this is a bit more complex, it is a model the ECM calculates based on the ET sensor, the intake air temp (IAT) and other factors. Head Temp is used within the ECM primarily for Spark Temp correction, for most combination it will run between 260-400F. Note: Heat Temp has been recently added to the PV channel list an is reported as HeadT. The last channel is Coolant Temp which is active on twin cooled and V Rod applications. Hope this info helps...
Thanks for the input. So a motor running at 250-270 and head temp 350-370 while cruising is good nothing to worry about?
Thanks
Rich
 
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Old May 30, 2023 | 11:40 AM
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Originally Posted by rsking45
Thanks for the input. So a motor running at 250-270 and head temp 350-370 while cruising is good nothing to worry about?
Thanks
Rich
Consider this… since some of the Trikes “normally” run 300-400 degs engine temps in summer weather, yours seems cool by comparison.
Bob
 
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