Electric vs mechanical fan

[86Peter454]

any of you guys pay for motor trend on demand?

the Engine Masters guys tested some of this and if i recall correctly. if going mechanical fan your gonna want a clutched fan.

the advantage to electric is its not on all the time when it is on the draw from the alternator will likely kill more power than the mechanical fan. (again that is if i remember correctly)

like someone else said pay attention to amp draw the lower the better really.

 

[shiftpro]

any of you guys pay for motor trend on demand?

the Engine Masters guys tested some of this and if i recall correctly. if going mechanical fan your gonna want a clutched fan.

the advantage to electric is its not on all the time when it is on the draw from the alternator will likely kill more power than the mechanical fan. (again that is if i remember correctly)

like someone else said pay attention to amp draw the lower the better really.

The Engine Master shows eventually all make it to youtube.
Yes I agree a mechanical fan is best it it has a clutch.
Most of the Engine Master's data I find only really applies to high rpm racing attitudes... not daily driver.
Like the one about 2.5" exhaust vs 3"... yes the 3" produced more power but not u til after 5000rpm.

The dented header show was pretty good and related to reality.

But your last remark about fans with low amp draw I can not agree with that. Low amp pull = low cfms...
High amperage alternators do use more power to spin, but I don't imagine it would offset a 20 lbs clutch and fan. Move up to
alternators with enough power to reliably weld and heck yeah you have to increase rpms under load!

 

[4WDKC]

if its working fine and your not searching for every last tenth at the track leave it. If its not working its a good time to switch but, you will need a fan with a shroud that covers 70% of the radiator. Fans without shrouds only work in situations where the radiator is bigger than needed resulting in only needing minor air flow to cool or low horsepower situations. My vette had LT1 fbody fans without the shroud and they couldnt cool it. I swapped to some Ford focus fans in their much smaller shroud cooled it fine.

 

[Casey Little]

Thank you all for the input. I think I'm just going to leave it alone. I guess if it's not broke don't fix it. I'm also running my temp sensor in the water outlet right above the thermostat is that ok or should I be running it in the intake or the head?

 

[shiftpro]

If you upgrade to a high compression big block then we can return to this conversation.

 

[86Peter454]

The Engine Master shows eventually all make it to youtube.
Yes I agree a mechanical fan is best it it has a clutch.
Most of the Engine Master's data I find only really applies to high rpm racing attitudes... not daily driver.
Like the one about 2.5" exhaust vs 3"... yes the 3" produced more power but not u til after 5000rpm.

The dented header show was pretty good and related to reality.

But your last remark about fans with low amp draw I can not agree with that. Low amp pull = low cfms...
High amperage alternators do use more power to spin, but I don't imagine it would offset a 20 lbs clutch and fan. Move up to
alternators with enough power to reliably weld and heck yeah you have to increase rpms under load!

i agree they often look at just wide open throttle situations.

but a lot of the info can still apply. when cruising down the road if your not spinning a fan off the crank then you have more power available if need be. usually your electric fans should not be on if you are going down the road. just when in traffic and drive threw line and such. this should net you better fuel economy (theoretically).

you are right the lower amps the lower the cfm the idea really would be to do you best to get the fan with the least amp draw that will still cool your motor. other option may be to run multiple fans but on separate switches. this would mean you could keep things cool with one fan but if things get really hot you just know you will sacrifice your power for keeping the engine cool.

i certainly dont think electric fans are a must have but i think they would be a decent upgrade if the price is right.

 

[shiftpro]

i agree they often look at just wide open throttle situations.

but a lot of the info can still apply. when cruising down the road if your not spinning a fan off the crank then you have more power available if need be. usually your electric fans should not be on if you are going down the road. just when in traffic and drive threw line and such. this should net you better fuel economy (theoretically).

you are right the lower amps the lower the cfm the idea really would be to do you best to get the fan with the least amp draw that will still cool your motor. other option may be to run multiple fans but on separate switches. this would mean you could keep things cool with one fan but if things get really hot you just know you will sacrifice your power for keeping the engine cool.

i certainly dont think electric fans are a must have but i think they would be a decent upgrade if the price is right.

My setup will be for a high compression 496. The Dakota digital control I have in the link can be set to have only one fan run unless more cooling is needed. I'll route the wiring so I can easily switch plugs like maybe twice a year so the 'aux' fan gets some use time. Try to wear out both fans more or less the same.

 

[4WDKC]

Thank you all for the input. I think I'm just going to leave it alone. I guess if it's not broke don't fix it. I'm also running my temp sensor in the water outlet right above the thermostat is that ok or should I be running it in the intake or the head?

I prefer it in the head so I can see what the temps are doing.

 

[Jrgunn5150]

I prefer it in the head so I can see what the temps are doing.

Same, I want to know at all times, closer to the combustion chamber.

 

[Arkansas_V8]

any of you guys pay for motor trend on demand?

the Engine Masters guys tested some of this and if i recall correctly. if going mechanical fan your gonna want a clutched fan.

the advantage to electric is its not on all the time when it is on the draw from the alternator will likely kill more power than the mechanical fan. (again that is if i remember correctly)

like someone else said pay attention to amp draw the lower the better really.

I pay for MotorTrend, and I am so damn excited about Top Gear August 30th.

 

[86Peter454]

I pay for MotorTrend, and I am so damn excited about Top Gear August 30th.

yo me too!

 

[Arkansas_V8]

yo me too!

I was pissed when it got pushed back from the 4th the first time.

Hoping they dont screw us again.


Like the new setup? I really like the new layout of the app.

I have been a member since Beta, it is way better now.

 

[roundhouse]

I pay for MotorTrend, and I am so damn excited about Top Gear August 30th.

I stopped watching it when Clarkson, May and the Hamster left
The replacement crew was not funny

But then their Grand Tour just wasn’t the same , it just wasn’t as funny as TG

Oh well nothing lasts forever

Mrs Roundhouse cares not a bit about cars but she loves watching top gear because it was so funny

 

[Arkansas_V8]

I stopped watching it when Clarkson, May and the Hamster left
The replacement crew was not funny

But then their Grand Tour just wasn’t the same , it just wasn’t as funny as TG

Oh well nothing lasts forever

Mrs Roundhouse cares not a bit about cars but she loves watching top gear because it was so funny

Seasons 2 to the end on the app, my wife is the same way.

She told me to tell you atleast they watch it with us. Lol

 

[Matt69olds]

Nothing beats a big engine driven fan. If electric fans were superior to engine driven fans my Cummins powered ram wouldn’t have a mechanical clutch.

The important part of this discussion is how the fan is controlled. My Cummins has a mechanical fan driven by the engine, but has a electric clutch controlling it. Until the engine is hot enough to need the fan, it doesn’t do much. Same thing with a thermal fan clutch, just isn’t as refined as the electric clutch. The fan basically free wheels until the engine is hot enough to engage the clutch.

As for mechanical fans robbing power, I have tried completely removing the fan and clutch from my 69 Olds at the track. There was ZERO difference in ET, or mph. This was on a Friday night test and tune, made a baseline pass, removed the fan, made a couple passes, and reinstalled the fan, also with no change. Thermal clutch fans just don’t take much power to drive them, until you need the added airflow.