Fan Disabled at higher speeds?
08-13-2007, 10:43 AM
#1
TECH Apprentice
Thread Starter
iTrader: (1)
Join Date: Oct 2005
Location: Port Charlotte, FL
Posts: 314
Likes: 0
Received 0 Likes
on
0 Posts
Fan Disabled at higher speeds? Does the PCM Disable the fans after you reach a certain speed. I have my fan 1 on temp set to 185, cruising on the highway my temp sits about 188. But I know the fan wont be of any use going 75mph. So I was wondering at what speed does it automatically cut the fans due to more airflow by speed then the fan creates CFM. Any help would be appreciated.
Josh
Josh
08-13-2007, 02:35 PM
#3
TECH Fanatic
Join Date: Mar 2004
Location: Laguna Niguel, CA
Posts: 1,017
Likes: 0
Received 0 Likes
on
0 Posts
Are you sure? Would this be true for a manual fan switch? or only when they are switched on by computer.
Would I be wasting my fan operating life by leaving them running while cruising above 35?
I would bet that they help past 35, but probably only up to about 55 or so. (The only way to tell would be to measure the speed of the fan and that would be the point at where the fan starts to become a hinderance vs a help.
Would I be wasting my fan operating life by leaving them running while cruising above 35?
I would bet that they help past 35, but probably only up to about 55 or so. (The only way to tell would be to measure the speed of the fan and that would be the point at where the fan starts to become a hinderance vs a help.
08-13-2007, 02:39 PM
#4
Originally Posted by gun5l1ng3r
Are you sure? Would this be true for a manual fan switch? or only when they are switched on by computer.
Would I be wasting my fan operating life by leaving them running while cruising above 35?
I would bet that they help past 35, but probably only up to about 55 or so. (The only way to tell would be to measure the speed of the fan and that would be the point at where the fan starts to become a hinderance vs a help.
Would I be wasting my fan operating life by leaving them running while cruising above 35?
I would bet that they help past 35, but probably only up to about 55 or so. (The only way to tell would be to measure the speed of the fan and that would be the point at where the fan starts to become a hinderance vs a help.
yes, its in the PCM. if i was on my laptop, i could show you a screen shot on HPtuners of the settings.
no, this doesnt apply to the manual fan switch.. with that, the fan is on, constantly... it only applies when its still PCM controlled like stock.
yes, its pointless to run the fan once you're moving over 35.
GM has done this with every computer controlled fan ive ever seen..
08-13-2007, 03:02 PM
#5
The fans are not shut off until about 55 MPH. The fans can STILL come on abouve 55 MPH if the vehicle gets extremely hot. #1 fan is limited to 30 MPH but can still come on abouve this speed.
If you are a traveling type you might look into a single fan setup which doesn't occupy the entire area of the radiator. This allows for more flow when the fans are not on.
The fan shroud helps to pull air through when the fans are on but limits airflow any other time. GM didn't even put shrouds on alot of cars until about 1967 or so.
--Screen Shot Attached --
Nothing exists but metric.
If you are a traveling type you might look into a single fan setup which doesn't occupy the entire area of the radiator. This allows for more flow when the fans are not on.
The fan shroud helps to pull air through when the fans are on but limits airflow any other time. GM didn't even put shrouds on alot of cars until about 1967 or so.
--Screen Shot Attached --
Nothing exists but metric.
Besides a seeping OHV water pump.
08-13-2007, 04:20 PM
#7
Originally Posted by MrDude_1
yes, its in the PCM. if i was on my laptop, i could show you a screen shot on HPtuners of the settings.
no, this doesnt apply to the manual fan switch.. with that, the fan is on, constantly... it only applies when its still PCM controlled like stock.
yes, its pointless to run the fan once you're moving over 35.
GM has done this with every computer controlled fan ive ever seen..
no, this doesnt apply to the manual fan switch.. with that, the fan is on, constantly... it only applies when its still PCM controlled like stock.
yes, its pointless to run the fan once you're moving over 35.
GM has done this with every computer controlled fan ive ever seen..
Nah, those MPH tables are V6 only if you read the print in the boxes. EFIL must have more settings than us with HPT for fans, as we can only run them by temperature
