LS cooling fan question

[mikeextrafast]

How is everyone turning there fan off and on are you guys letting the ECU control it or you useing a seprate controller? Iam have a LS3 with dual fans

[Schwartz Performance]

We've done a sending unit in the head to turn on the ground for a fan relay or let the computer turn it on. If you have AC then run it thru a trinary switch.
-Dale

[armourmark]

Letting the ECU control them both.

[mikeextrafast]

Do you run one just to cool engine and bring the other one when the ac is turned on ? Was thinking about useing some type of fan controller

[garys 68]

One fan by the ecu, the other with a trinary switch and/or manually adjustable temp sensor.

[Later-A-body]

I have a Lincoln Mk VIII fan installed for my LS swap, single fan but dual speed. My intention was to allow the ECU (E38) control both low and high speeds of the fan. According to Speartech, the ECU has the ability to do this, and can be reprogrammed to adjust the temperatures that activate each speed if you wire it up properly. Has anyone accomplished this set up?

[joshtownsend]

thats an ls2 pcm.. 2005 and above y body

[hifi875]

was using a spal pwm but now using the pcm that came with my terminator efi. works alot better. dang spal piece would default back to factory settings all the dang time.

[cubicylndr16]

Stock pcm such as a 0411 has the ability to be programmed to control 2 speeds. You'll need to re-pin one wire on the harness and have the pcm programmed. Check out lt1swap.com for info.

[DippedInSauce]

I have a Lincoln Mk VIII fan installed for my LS swap, single fan but dual speed. My intention was to allow the ECU (E38) control both low and high speeds of the fan. According to Speartech, the ECU has the ability to do this, and can be reprogrammed to adjust the temperatures that activate each speed if you wire it up properly. Has anyone accomplished this set up?

I've been running the Mk VIII fan for years. Since the 1st gen has limited radiator realistate its one of the best fan options IMO. It pulls more air than most duel fan systems. I've allowed my Speartech ecu to control its operation for the past 5 years with zero issues. I spoke with an engineer at Four Seasons (the original fan motor was manufactured by Siemens, Four Seasons now manufactures them in Canada)
who informed me that in the factory application the fan rarely utilized the low speed option. He said its perfectly fine for it to run on high speed all day long. The only issue I've encountered is with the factory motorcraft connector. It tends to heat up and partially melt over time due to the fans high power draw. I discovered the best fix was to eliminate the connector and hard wire it.