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Discussion Starter #1
I went to houston for the weekend of the 4th of july, and on the way down I watched my temp gauge fluctuate often. This bothered me so I called my mechanic and we talked about it. we came to the conclusion that it might be the thermostat. so in houston i had it replaced. But nothing changed. Im using the builtin diagnostic settings on the gauge cluster and ive seen temp on the road go from 105 C to 111 C. And with my conversion that means i was running between 221 F and 231 F. Does that seem a little off to anyone?
Any answer would help.
 

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One thing to keep in mind is that the gauge is reading the cylinder head temperature and not coolant temp. That is one reason it flucuates as it does. The cylinder head temp quickly reponds to any increase in power output.

Under 10+ psi boost I've seen my cylinder head temps jump 30°F in a matter of seconds. I can't recall what the actual numbers were, but I could look back thru some of my logged data and see what temps I'm running.
 

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You're all right (from the standpoint of damaging the engine) as long as the coolant doesn't boil. 221 deg seems a little high, but DePue makes an interesting point and maybe that accounts for it. The head itself would always have to be hotter than the coolant or no heat transfer could take place. So maybe while the head is 221, the coolant is a nice, cool 195.
 

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I agree its a bit high, but you may have an air pocket somewhere. Check into that as well, some cars are very prone to that ( subaru ). Have you flushed the system lately or anything like that?
 

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Discussion Starter #6 (Edited)
It hasnt been flushed but ive got a new temp sensor on the way. When I install the new sensor im going to flush it. About the air pocket, I cant see that happening with the built in de-gas chamber, but anything can happen. And about the cylinder head temp, I dont know because when the temp on the diagnostics changes, so does the temp gauge.
 
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