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Is 178F too cold?

Old Mar 1, 2003 | 09:17 PM
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Question Is 178F too cold?

In the never ending quest to run my car cooler, I have gotten to the point now where I can keep the car running at 178F with Evans NPG+. But in retrospect isn't the 13B happiest at 190F (best power output)? If this is true then could 178F be too cold? Would running 12 degrees cooler extend the engine life with peak power as a trade off?
I guess the biggest questions are:
1. Will cooler definitely extent the engine life if so, by how much (given similar driving patterns).
2. How much power would one lose at these temps?
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Old Mar 1, 2003 | 10:28 PM
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wouldn't this be too cold and actually be bad for the engine?
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Old Mar 1, 2003 | 11:12 PM
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The question is can anyone quantify what's "bad"?
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Old Mar 1, 2003 | 11:33 PM
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I would wait and see what temps its running at in the warmer spring and summer months. If the engine is cooler, depending on the temp at speed, it might be adding more fuel in small amounts thinking the engine isn't fully warmed up. Being excessively rich isn't good for the side seals according to mazdatrix, but I don't think the ecu seeing 178 is going to add very much extra fuel to be considered excessively rich.

When are you going to be making your way back up toward Atlanta?

Tim
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Old Mar 2, 2003 | 01:33 AM
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The stock thermostat begins to open at 177F so I'd think 178F is perfectly fine, although you might gain a little power/fuel efficiency at 190F. I think as long as you're anywhere between 177F-200F then you are completely ok. The car won't run excessively rich at 178F, that is considered operating temperature so the mixture is normal.
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Old Mar 2, 2003 | 01:33 AM
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The stock thermostat begins to open at 177F so I'd think 178F is perfectly fine, although you might gain a little power/fuel efficiency at 190F. I think as long as you're anywhere between 177F-200F then you are completely ok. The car won't run excessively rich at 178F, that is considered operating temperature so the mixture is normal.
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Old Mar 2, 2003 | 01:49 AM
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hmmmm, if your not at at least 180f. your not out of warmup mode which means your double throttle valves are not gonna open as well as your maps being different (richer) and the rest of the things when your not warmed up. All these things can be fixed easily though such as just taking out the double throttle butterfly flaps or just capping the actuator (sp?) or buy just buying a power fc and turning all the adjustments to 0 for the warm up cycle. Then again, 178-179 is pretty much the same thing as 180 and idk if the sensor will actually tell the difference. In anycase, I doubt that you'll actually extend the life of your engine by that much but its good that you got your temp down.


Last edited by skunks; Mar 2, 2003 at 01:52 AM.
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Old Mar 2, 2003 | 08:45 AM
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Originally posted by Tim Benton
I would wait and see what temps its running at in the warmer spring and summer months. If the engine is cooler, depending on the temp at speed, it might be adding more fuel in small amounts thinking the engine isn't fully warmed up. Being excessively rich isn't good for the side seals according to mazdatrix, but I don't think the ecu seeing 178 is going to add very much extra fuel to be considered excessively rich.

When are you going to be making your way back up toward Atlanta?

Tim
I will be moving to Atl in the May-June time frame, so I'll see you guys around more often.
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Old Mar 2, 2003 | 08:47 AM
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Originally posted by skunks
hmmmm, if your not at at least 180f. your not out of warmup mode which means your double throttle valves are not gonna open as well as your maps being different (richer) and the rest of the things when your not warmed up. All these things can be fixed easily though such as just taking out the double throttle butterfly flaps or just capping the actuator (sp?) or buy just buying a power fc and turning all the adjustments to 0 for the warm up cycle. Then again, 178-179 is pretty much the same thing as 180 and idk if the sensor will actually tell the difference. In anycase, I doubt that you'll actually extend the life of your engine by that much but its good that you got your temp down.
FYI, I did remove the DT, and will be installing the AEM EMS in the next couple of months.
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Old Mar 2, 2003 | 09:06 AM
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I think the most important aspect (beside running rich) is the oil temp. Depending on what weight oil you are running there is a *fairly* narrow range of temperature where it functions optimally. That alone could have a dramatic effect on wear over time. I really don't know where the rotary is most efficient, but around 200F is a benchmark for just about all internal combustion engines.

It's pretty impressive that you are able to keep the temps down that low! When was the last time you heard a 3rd gen owner concerned about runnning too cold?! Just wait until August.........
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