High output alternator for G50

[Trumpkin]

I have a electric fan installed on my G50. It pulls quite a few amps. Has anyone upgraded the alternator for this reason or other reasons? Also who could do something like this? Can I buy one somewhere? I know some do not feel this mod is worth it, but non the less, Any input would be welcomed.Thanks

[Infinitiguy19]

How did you install the fan?

When does it turn on?

Give us as much info as possible.

And there are aftermaret souluions, I remmber I saw an old thread some where around here so look around.

[Trumpkin]

It's a universal fan mount. It uses a thermostatic switch to turn on and off. It makes a difference with no fan clutch.

[Infinitiguy19]

But where did you find the room to mount it do you have pics?

Is there any way to have the fan stay on after turning off the car?

[Trumpkin]

Once you take out the stock fan/clutch and schroud there is plenty of room.It depends on how you wire it. It is a thermostatic switch.

Thread is way off topic!

[silver2k2]

any local starter electrical motor rebuilder should be able to upgrade your stocker. I have done this before with good results. They take your alternator and add custom windings

Example

http://www.highoutputalternator.com/customshop.htm

[Trumpkin]

Thanks. I am running a reman now. Already went bad once. But the car sits. Maybe I'll get a quote on a oe and upgrade that.

[maxnix]

Don't see any benefit as the viscous clutch will only engage when there is not enough air moving, usually at idle in hot weather and never on the highway or at WOT.

However, the horsepower drag from turning the higher capacity alternator required to power it will always be present.

[Infinitiguy19]

Once you take out the stock fan/clutch and schroud there is plenty of room.It depends on how you wire it. It is a thermostatic switch.

Thread is way off topic!

So you have completely removed the OEM mechanical fan and added a electric fan right?

There is no gain beyond not having to replace the fan clutch which is a rare failure.

[maxnix]

There is no gain beyond not having to replace the fan clutch which is a rare failure.

Actually, I think there is a net power loss as now the engine is powering a larger alternator continuously.

Q45tech has an interesting post that mentions the same thing.

[Skibane]

Actually, I think there is a net power loss as now the engine is powering a larger alternator continuously.

"Continuously" is probably an overstatement. The alternator only produces drag when it is actually generating current...and the fan only draws current when it is actually running. Typically, the thermostat is set to turn on the fan only when supplemental cooling is needed. The rest of time, the fan's contribution to alternator drag is nil.

Meanwhile, a belt-driven fan is always producing some drag, because the viscous clutch never completely disconnects the fan from the pulley - The fan "freewheels" at some speed that is lower than engine speed, drawing some engine power in the process.

My biggest problem with electric fans is that they rarely are capable of moving as much air as a properly-functioning belt-driven fan. There are times when you actually need 5 horsepower worth of air movement - and the laws of physics say that a half-horsepower electric fan motor just isn't capable of accomplishing the same thing.

[Q45tech]

Be careful about so called high output alternators. Important to understand and create a graph of amperes per alternator rpm and divide by pulley ratio............to equate to engine rpm.

Having higher current at 2000 engine rpm doesn't do much good with idling in summer traffic.

[Rex]

From my days in "excessive car audio" a couple decades ago, I'm aware of some of the options for higher output alternators. My biggest concern if I were looking at one for a Q45, would be the RPM's it would see. Since so many were on non-daily drivers, I can't say what the real world life span is, but would think they wouldn't like seeing ~6500 RPM's very much.

[Denver90Q]

Thanks. I am running a reman now. Already went bad once. But the car sits. Maybe I'll get a quote on a oe and upgrade that.

How many amps are you drawing and how old is your battery?

[Trumpkin]

Having higher current at 2000 engine rpm doesn't do much good with idling in summer traffic.

Rush hour traffic is not a concern.

[Trumpkin]

How many amps are you drawing and how old is your battery?

Brand new optima, from what I remember it's 17amps with fan on.Do I even need to worry about it? Or should I let it ride?

[Denver90Q]

17 amps is only about 200 watts (like two light bulbs or highbeams on headlights). I wouldn't worry about it. Those alternators are a pain to take off.

[Q45tech]

Interesting that most alternators are only 50-55% efficient so that 746 watts needs 2 horsepower to turn so 110 amperes out needs 4.36 HP of input.

"Efficiency of automotive alternators is limited by fan cooling loss, bearing loss, iron loss, copper loss, and the voltage drop in the diode bridges; at part load, efficiency is between 50-62% depending on the size of alternator, and varies with alternator speed"

http://www.windstuffnow.com/ma...s.htm

[maxnix]

Rush hour traffic is not a concern.

So you drive only at night? Headlights then are an extra load.