Cooling Fans w/LME tune

[Dxlnt1]

I know this has been discussed but I can't find the thread. Since I now run the 93 octane LMS tune, of course the fans run ALL THE TIME! I am sick of it. That is causing me to want to downgrade the loaded tune to the 91 4x+.

My question

1. Has LMS changed the set point to trigger the fans to run as much?

2. What temp thermostat are you 93 tune guys running?

3. Is there any benefit or trade off is I install the 160 thermostat and keep the tune?

4. Is LMS targeting an unrealistic engine temp, therefore forcing fans almost into an on/off mode small donkey-like animal opposed to modulating mode.


My car never runs above 190 degrees. I currently have the 170 t-stat installed. On a cold start, the fans come on at roughly 140 degrees. Then anything above 170, they are at full blast. Including when running down the highway on a cold day.

[ZSHO]

I recall you having the same issue a while back with the fans running constantly,that should not be happening IMO,the only time my fans come on is if the a/c or front defroster is set to on or auto on a cold start,would also check your HVAC controls are not set to on or auto on your custom radio display.  Z

[BiGMaC]

I'll try to answer as I had the same problem with LMS v8 for the '13+ ...In v8 LMS treats this, an adjustment for fan cut on as a request item only requiring the lower temp T-stat.

1. Yes they lowered it...and I believe they are always on high. They contend the fans last longer if they don't cycle and that the engine will take longer to heat soak... Eventually the temp will reach the temp it can maintain for a given set of operating conditions though.

2. I use the 91 octane version of the v8 tune. But fan "cut on" temp is set the same if you have the LMS T-stat as I understand it. I have the LMS 160 degree T-stay, but don't notice the difference from the 170 degree after commuting in a PHX summer.... Both seem to keep the coolant temps about 7-10 degrees cooler on the average in temps over the roadway in excess of 125 degrees... There could be more difference in a milder climate and before heat soak.

3. Yes, but in the short run... See #1 above

4. See above... There is some benefit... Quicker cooling (even when the engine is turned off and only convection is moving coolant. This is most beneficial for short trips or cooling between runs at the strip.

Here's what I did... Just called them and told them the fans were driving me crazy... They immediately sent me a tune with the fan cut on at a higher temp and adjusted it so the fans are on low for a while first. I am not sure what the exact temp or conditions are required for the fans to run on high. Anyway... It's fixed that simply. You'll have to decide on the T-stat temp. For me it was a no brainer living in the desert.

I'm sure better insights will come from others.

[SHOdded]

Z, BiGMaC, you guys rock!  Great info.  dx, get LME's signoff on what you want to do, and you'll be fine.  No need to change TStat or anything!  You'll get still get a little additional passive cooling, not a bad thing for tuned engines anyway.

[Dxlnt1]

I recall you having the same issue a while back with the fans running constantly,that should not be happening IMO,the only time my fans come on is if the a/c or front defroster is set to on or auto on a cold start,would also check your HVAC controls are not set to on or auto on your custom radio display.  Z

I think LMS just reloaded my tune. As I recall, there were issues with their server and my tunes. Seems to happen every time there is a tweak. I have to call them to reload so I can load onto car. I do keep my HVAC system on. Mostly just the fan to keep air moving through system. No heat or AC request most times.

I'll try to answer as I had the same problem with LMS v8 for the '13+ ...In v8 LMS treats this, an adjustment for fan cut on as a request item only requiring the lower temp T-stat.

1. Yes they lowered it...and I believe they are always on high. They contend the fans last longer if they don't cycle and that the engine will take longer to heat soak... Eventually the temp will reach the temp it can maintain for a given set of operating conditions though.

2. I use the 91 octane version of the v8 tune. But fan "cut on" temp is set the same if you have the LMS T-stat as I understand it. I have the LMS 160 degree T-stay, but don't notice the difference from the 170 degree after commuting in a PHX summer.... Both seem to keep the coolant temps about 7-10 degrees cooler on the average in temps over the roadway in excess of 125 degrees... There could be more difference in a milder climate and before heat soak.

3. Yes, but in the short run... See #1 above

4. See above... There is some benefit... Quicker cooling (even when the engine is turned off and only convection is moving coolant. This is most beneficial for short trips or cooling between runs at the strip.

Here's what I did... Just called them and told them the fans were driving me crazy... They immediately sent me a tune with the fan cut on at a higher temp and adjusted it so the fans are on low for a while first. I am not sure what the exact temp or conditions are required for the fans to run on high. Anyway... It's fixed that simply. You'll have to decide on the T-stat temp. For me it was a no brainer living in the desert.

I'm sure better insights will come from others.

Cali climate pretty mild for the most part. Nothing like that desert you call Phoenix. I will call LMS to inquire. I would be okay with fans running all the time, just not on FULL. That seems to be a killer to them And yes less cycling does prolong life. So theoretically the fans can be on and just the full speed trigger raised. The noise from these things sux. I get compliments the car looks like a BMW but sounds like a Ford, lol. Not sure how to take it.

[AJP turbo]

Would really be a hard argument to prove one way or another...would have to leave the fans on and have another car cycle the fans to the point of failure which nobody has done side by side as far as i know....ill let my fans cycle on/off only when needed when the radiator and water pump and natural airflow are not adequate....less duty cycle and startups out weigh  constant running in my book

[ZSHO]

DX would also try to rule out having air in your system,especially after install of the 170 stat,otherwise follow the above mentioned because the cooling fans only run at full speed,just a thought brother.  Z

[Dxlnt1]

DX would also try to rule out having air in your system,especially after install of the 170 stat,otherwise follow the above mentioned because the cooling fans only run at full speed,just a thought brother.  Z

No air in system. This only an issue with the 93 octane tune. The 170 was put on when I first got car.

[AJP turbo]

The fans are variable speed...i was surprised but the stock tables never have 0's in any area of the ect tables...meaning they should always be on...they go from 0-100%....lowest value is 9 even when cold......its been awhile since ive been stock so i dont know if they s*** off or not