Considering lower T-stat - do I have this right?

[skates15]

Hello,
After reviewing the various threads on changing to a 192 or 180 Tstat, do I have it right that I will need to unlock the PCM and have a tuner change the fan curves?

Second, regarding the fan curve, if my desire is to not have the fans constantly running in hot weather (90-100f) then would a 192 Tstat work best, opening at 190? I don't want to switch T stat back to stock during winter, so I was thinking 190 is a good medium.

I do plan to take the AGS slots out, leaving the top and bottom in place during summer, then putting them all back during winter with no changes to the Treat or fan curve.

Looking for a sweet spot so that I don't have to fiddle with it across winter/summer and the fans not having to work so hard.

 

[Wild one]

Both will work with-out tuning,but in slow moving rush hour traffic on a hot day they'll operate at close to stock temps,but as soon as you turn on the A/C ,or as soon as you start rolling with a little speed and there's air movement across the rad the temps will drop.You don't have to spring for tuning if you don't want to,as long as you know what happens and the ways to bypass the issues
In your case if you don't want to change it yearly a 192 is a good middle of the road option

 

[Mojo88]

You have a PWM fan, (PWM stands for pulse width modulation). In short, it's a signal the header sends to the fan to tell it how fast to spin. The controls for a PWM fan are in table 18171 (HPTuners), "PWM Desired ECT" (shown in the pic below). In this table, the axis (on the left) is the ambient air temp and the values inside the cells are the desired coolant temp. The pic shows the stock settings. The engine is designed to run HOT, so your fan will do everything in its power (in other words, it won't run until ECT is ~221*) to keep your engine HOT.

I installed a 180* stat in my 2019 RAM 5.7L. And then (since I have HPTuners and unlocked PCM) I adjusted the fan settings down to 190*. But my ECT (engine coolant temp) will reach ~193* before fan comes on and shutters open up, quickly cooling to ~186* (normal cruising temp).

If ambient temp reaches 106*, then your fan will come on at ~212* ECT. I believe fan is always on when A/C is running, but not 100% sure...............

My AGS are fully intact and operational. I believe they are a benefit, especially in colder weather, to help engine warm up quicker.

 

[skates15]

Thanks for the replies, great info. Looking at the cost for an unlocked PCM, tuner, cable is pretty expensive, unless I was planning on further tuning, which I'm not at this time.
I think I will go with the 192, remove some slats, engage A/C when ambient is high. Winter I will add the slats back.

If I go with other mods down the road which require a tune, then I may go with hemifever custom, asking them to change the fan curves at the same time.

That HP tuner graph is fascinating.

 

[skates15]

You have a PWM fan, (PWM stands for pulse width modulation). In short, it's a signal the header sends to the fan to tell it how fast to spin. The controls for a PWM fan are in table 18171 (HPTuners), "PWM Desired ECT" (shown in the pic below). In this table, the axis (on the left) is the ambient air temp and the values inside the cells are the desired coolant temp. The pic shows the stock settings. The engine is designed to run HOT, so your fan will do everything in its power (in other words, it won't run until ECT is ~221*) to keep your engine HOT.

I installed a 180* stat in my 2019 RAM 5.7L. And then (since I have HPTuners and unlocked PCM) I adjusted the fan settings down to 190*. But my ECT (engine coolant temp) will reach ~193* before fan comes on and shutters open up, quickly cooling to ~186* (normal cruising temp).

If ambient temp reaches 106*, then your fan will come on at ~212* ECT. I believe fan is always on when A/C is running, but not 100% sure...............

My AGS are fully intact and operational. I believe they are a benefit, especially in colder weather, to help engine warm up quicker.

View attachment 564139

Hopefully the HPTuner mafia won't come after you for posting the pic with description. I followed your posts over at their forum.

 

[Wild one]

Thanks for the replies, great info. Looking at the cost for an unlocked PCM, tuner, cable is pretty expensive, unless I was planning on further tuning, which I'm not at this time.
I think I will go with the 192, remove some slats, engage A/C when ambient is high. Winter I will add the slats back.

If I go with other mods down the road which require a tune, then I may go with hemifever custom, asking them to change the fan curves at the same time.

That HP tuner graph is fascinating.

As far as i know Sean/Hemifever is still stuck in the old days,and only tunes with Diablo,and unless you're somebody big in the drag racing world,you basically only get a generic tune from him or Greene,in other words there's better tuners out there if you go looking.

 

[skates15]

As far as i know Sean/Hemifever is still stuck in the old days,and only tunes with Diablo,and unless you're somebody big in the drag racing world,you basically only get a generic tune from him or Greene,in other words there's better tuners out there if you go looking.

Good looking out. Yeah, no drag racing here. HP does seem easier from what I've learned so far.

 

[Mojo88]

Hopefully the HPTuner mafia won't come after you for posting the pic with description. I followed your posts over at their forum.

Hahhahahaa, that's a good one. They should be paying me for the publicity.....

But don't worry about them, they get plenty of money, as you know. With my unlocked PCM, MPVI3 dongle, cable and credits (engine and trans), I'm into them for close to $1600. There is a LOT to learn, but it's actually fun and interesting.

I was initially like you, thinking the expense might not be worth it, and I wasn't go do much 'tuning', so why spend the money. But the MDS in my truck just aggravated me so much, I couldn't stand it, and the only viable way to shut it off is in the tune. I used the manual gear selection method to disable MDS for a few months, but that was a PITA.

So far, my changes using the HPTuners;
disabled the MDS,
adjusted the fan settings (installed 180* stat),
adjusted the throttle activation,
adjusted the shift tables (shifts engage later, not so early),
and just yesterday I entered in a new timing table for part-throttle driving (from SavaageRandy on YouTube). He says it gives him better gas mileage, basically a 4* advance.

 

[skates15]

So far, my changes using the HPTuners;
disabled the MDS,
adjusted the fan settings (installed 180* stat),
adjusted the throttle activation,
adjusted the shift tables (shifts engage later, not so early),
and just yesterday I entered in a new timing table for part-throttle driving (from SavaageRandy on YouTube). He says it gives him better gas mileage, basically a 4* advance.

Those all sound great and worth while. Any idea what the mileage might provide with the 4* advance?

 

[Mojo88]

Here's the vid I watched. I heard him mention "better gas mileage" and I was hooked, haha. Plus, I like the fact that this timing table is for part-throttle only, which is where 99.999% of my driving is. I don't beat on my truck at all.

One thing I noticed RIGHT AWAY is more pep at take-off. The truck really liked that extra timing at part-throttle. I'm almost tempted to try a little more, but I won't do that until I have some way of measuring the results. I guess I could data-log and see if the knock sensors are activated, but I'm not savvy enough yet to start pushing the boundaries.

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