Help with 180 Thermostat and setting fan controls.

Installed a 180 degree T-Stat in my 2015 Hellcat. After the install I calculated the following values

1. Low Speed ECT - 185
2. Med Speed ECT - 194
3. High Speed ECT - 194

This was based on some trainings from The Tuning School books/videos as well as scouring YouTube and also on these forums (did quite a few searches, most results were jeep related).

I applied these values to the following Modes:

1. High Vehicle Speed Mode
2. Low Vehicle Speed Mode
3. A/C On

Here is a screen cap of the System -> Fans section as it currently sits in the tune:
Attachment 102572

So from start of the car until 221 degrees the PWM did not change. When it did change it was too little too late. Coolant expanded that it hit overflow.

Attachment 102573

Wasn't happy that I need to clean this...
Attachment 102574

Checked the hose and tried to squeeze it, wasn't fungible which means the T-Stat opened and coolant was flowing. However the fan didn't turn on till later. My expectations were that once the tune was adjusted and the temperature was detected the fans would immediately turn on and begin cooling the vehicle. I decided to go for a drive, get some data and see what is going on.

Are my expectations wrong? Anyone wanna school me on how the cooling system works in these cars? Why don't I see 185? Could I have a bad t-stat? I did notice that while driving on the highway under no load the temps they stay below 194 and do hit 185 on a long stretch. Did I miss something to adjust in the tune? What have you guys done to adjust the tune for the T-Stat. I've attached my tune and my log file just in case anyone can do a mini dig and find something I didn't do right?

Attachment 102575
Attachment 102576

Change PWM Desired ECT. Notice Fan Type on a Hellcat is PWM not 2 or 3 Speed Relay. The tables you changed aren't for PWM fan control

Quote:

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Originally Posted by fumanchu182

Installed a 180 degree T-Stat in my 2015 Hellcat. After the install I calculated the following values

1. Low Speed ECT - 185
2. Med Speed ECT - 194
3. High Speed ECT - 194

This was based on some trainings from The Tuning School books/videos as well as scouring YouTube and also on these forums (did quite a few searches, most results were jeep related).

I applied these values to the following Modes:

1. High Vehicle Speed Mode
2. Low Vehicle Speed Mode
3. A/C On

Here is a screen cap of the System -> Fans section as it currently sits in the tune:
Attachment 102572

So from start of the car until 221 degrees the PWM did not change. When it did change it was too little too late. Coolant expanded that it hit overflow.

Attachment 102573

Wasn't happy that I need to clean this...
Attachment 102574

Checked the hose and tried to squeeze it, wasn't fungible which means the T-Stat opened and coolant was flowing. However the fan didn't turn on till later. My expectations were that once the tune was adjusted and the temperature was detected the fans would immediately turn on and begin cooling the vehicle. I decided to go for a drive, get some data and see what is going on.

Are my expectations wrong? Anyone wanna school me on how the cooling system works in these cars? Why don't I see 185? Could I have a bad t-stat? I did notice that while driving on the highway under no load the temps they stay below 194 and do hit 185 on a long stretch. Did I miss something to adjust in the tune? What have you guys done to adjust the tune for the T-Stat. I've attached my tune and my log file just in case anyone can do a mini dig and find something I didn't do right?

Attachment 102575
Attachment 102576

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can you post the formula you used for calculating the three ranges ?

Quote:

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Originally Posted by tbrtuning

Change PWM Desired ECT. Notice Fan Type on a Hellcat is PWM not 2 or 3 Speed Relay. The tables you changed aren't for PWM fan control

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This makes a world of difference. There were two values in the table for Ambient air temperature, I set both values to 185. Theory being that still want the T-stat to open at 180 to circulate and then the 185 should get the fans going. Fans kicked in as expected and I didn't see a temp above 192 on "spirited" driving. This is a beautiful thing, should help at the track, I owe you some beers! Do you have any recommendations or is my theory sound? I also checked on what fan type I had on my ScatPack and you are correct. The default was "Relay 2 Spd", these are just growing pains migrating from one to another.

Attachment 102581

185 or a little higher should work good. If you find the fans running more than you would like just bump it up some and if you want to you could use the ambient to set to like 190 when hot out and let it target something cooler in cool weather

So based on some instructions in a training course I took you take your thermostat and add +5 to it. So you have a 180 T-Stat, means that you want to set 185 as the temperature in which the fans come on so you cool fluid that is circulating. The +9 for the medium/high settings is based on the fact that thise values were +9 originally in the stock tune. However as discovered this is for non PWM fans, etc. I modified the PWM desired ECT table and set both values. Ill be monitoring and if I dont like the load on the fans I?ll set it to 190. So far the temp hasnt risen vastly at all and am happy with the result.

Quote:

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Originally Posted by fumanchu182

So based on some instructions in a training course I took you take your thermostat and add +5 to it. So you have a 180 T-Stat, means that you want to set 185 as the temperature in which the fans come on so you cool fluid that is circulating. The +9 for the medium/high settings is based on the fact that thise values were +9 originally in the stock tune. However as discovered this is for non PWM fans, etc. I modified the PWM desired ECT table and set both values. Ill be monitoring and if I dont like the load on the fans I?ll set it to 190. So far the temp hasnt risen vastly at all and am happy with the result.

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can you screen shot the new settings, i just installed a ron davis rad. in my challenger, an have a 2 fan brushless setup. 190 tstatl looking to adjust

Quote:

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Originally Posted by fumanchu182

So based on some instructions in a training course I took you take your thermostat and add +5 to it. So you have a 180 T-Stat, means that you want to set 185 as the temperature in which the fans come on so you cool fluid that is circulating. The +9 for the medium/high settings is based on the fact that thise values were +9 originally in the stock tune. However as discovered this is for non PWM fans, etc. I modified the PWM desired ECT table and set both values. Ill be monitoring and if I dont like the load on the fans I?ll set it to 190. So far the temp hasnt risen vastly at all and am happy with the result.

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did you set both values to 185 or what did you put for each value (89.6 , 105.8)?

that which you quoted is nonsense

and do not use F

using the native values is crucial in the fan tune