Fuel Article - Quadzilla Adrenaline - Optimal Engine Temperatures for Efficiency

[Mopar1973Man]

Quadzilla Adrenaline - Optimal Engine Temperatures for Efficiency

Optimal Coolant Temperature - 190℉ 

Factory thermostats set to either 190℉ or 192℉ are fine and will perform satisfactorily for most Quadzilla Adrenaline owners. For the people up north, it's possible to see coolant temperatures drop out below 180℉ because of the natural efficiency of the 24V and at idle the Cummins ISB tends to run cooler. When coolant temperatures start dropping the thermodynamics of the engine will shed more of the heat of the burning fuel back into the excessively cold coolant jacket.

Experimental 200℉ thermostat

I've been running a 2012 6.7L 200℉ thermostat for the winter of 2023. I'm using a Gates thermostat and the operational range of the thermostat is from 199℉ to 210℉ roughly. This brought up the block and cylinder head temperature and I'm finding the engine load is reduced about 4% at 65 MPH. For the winter time, I was seeing -7℉ for the 2023 winter and with the added temperature I was able to gain MPG's still in the colder air. 

 

NOTE: Warmer coolant temperatures will affect, Intake Air Temperatures, Fuel Temperatures, 

Engine Oil Temperature 

If your timing is correct you should have an Engine Oil temperature of about 30℉ to 35℉ lower than coolant. A stock 190℉ thermostat will have engine oil temperatures of 160℉ to 170℉ with correct timing. As for the Experiemential 200℉ thermostat, you will see 170℉ to 180℉ for engine oil temperatures with correct ignition timing. If the engine oil temperature rises to coolant temperature or beyond then your timing values are wrong and could be either too retarded in timing or too advanced in timing.

Engine Oil Temperature and Timing

You can use the transmission sensor of the Quadzilla into the extra port on the top of the oil filter housing. Do not use any sealants or tapes the brass body needs to have a clean ground connection to be accurate.

Retarded Timing

Too retarded the generation of the fuel burn will occur too late and add heat to the coolant jacket at the cylinder level and this added heat will reduce the performance of the oil cooler.

 

Advanced Timing

Too Advanced you'll notice the engine oil temperature will rise because most Quadzilla Adrenaline owners create negative torque tunes with excessive timing which will transfer heat energy to the cylinder jacket. Again this affects the performance of the oil cooler to exchange hot oil into an already warmer coolant jacket at the cylinder level. 

 

Intake Air Temperatures (IAT)

The Optimal intake Air Temperature (IAT) is 80℉ to 140℉ for Efficiency

Don't get me started with "Cold Air Intakes" and "Cold Air is Denser". I'm learning that for efficiency reasons you need to have warm air to aid in efficiency more so in the dead of winter. We are not running wide open throttle we are trying to reduce the amount of fuel being burnt and boost pressures at cruise state. This knowledge comes from my High Idle Switch and the MPG mode. Bringing the actual intake temperature up will aid in converting the fuel mist to a fuel vapor and ignition fairly rapidly. The colder the intake air temperatures the longer time is required to convert liquid fuel to vapor stage for ignition also part of the fuel will not completely vaporize and never really burn under light loads. Hence we add some warmth back to the intake air temperatures and fuel vaporizes better and ignition occurs with less advancement and less wasted fuel. I've noticed with the 200℉ thermostat the Intake Air Temperature will be higher which has helped keep Intake Air Temperatures above 80℉ through most of the winter.

Fuel Temperature (Quadzilla Adrenaline Only)

The Optimal Fuel Temperature (Quadzilla Adrenaline Only) is 80℉ to 140℉ for Efficiency

 

Flash Point of Diesel Fuel - 125℉ to 180℉ depending on other factors of distilling and additives used.

 

Excessively cold fuel takes more time to change from a liquid state to a vapor state. Then excessively high fuel temperatures tend to create asphaltenes which is the black material you'll find in the stock fuel filter or possibly aftermarket filters. High fuel temperatures will put stress on your PSG unit on top of the Bosch VP44 injection pump. My stated fuel temperature range you find mirrors the Intake Air Temperature. This is because both the fuel temperature and Intake Air Temperature will match more times than not as long as the factory fuel filter housing is still in place and you   The other part of the trick is NOT to have your fuel pickup tube in the fuel sender basket, this happens to be the hottest fuel being returned from the back of the head which can be hot enough to create the asphaltenes. Using a draw straw in the main fuel tank will have cooler fuel temperatures which can reduce the creation of asphaltenes and extend your fuel filter life to 60,000 miles to 80,000 miles with no problem. Cooler fuel of course is better for the PSG unit on top of the Bosch VP44 injection pump.

 

NOTE: Transmission Temperature is Engine Oil Temperature.

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[Doubletrouble]

 Great write up @Mopar1973Man, I to noticed a difference over the winter in regards to the intake air Temps. Once I installed my winter front my IAT came up considerably and she ran better, better mpg's and a bit better heat from the vents as well as faster initial warm up. I am still running the stock 190° thermostat and noticed these differences with no tuner.