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Discussion Starter · #1 ·
Are there any alternators that are a direct fit with our stock alternator? Probably some brackets need to be fabbed, but I'm just wondering.

Been reading about race alternators which disengage when you go WOT. So you run off the battery during WOT but in other times it's a normal alternator (kinda like how the a/c disengages when you go WOT)
 

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While I can't answer you about a replacement, superior alternator, I can tell you this: You can easily rig a flip switch that cuts power to the alternator off, so there's like no resistance/drag. If it's not used often, you can turn the alty off for over an hour on a good battery and never notice the difference when you turn it back on. (batty will recharge) Great idea for drag racing....

*Edit*
Also, I have only heard of upgrading an alternator when used in car audio applications.
 

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Discussion Starter · #3 ·
Hmm so if I rig something like that to my throttle pedal so it will turn my alternator off when I fully depress the pedal, that would be the best.
 

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pio!pio! said:
Hmm so if I rig something like that to my throttle pedal so it will turn my alternator off when I fully depress the pedal, that would be the best.
Yeah, about that........
lol

I'd just as rather take the 10 minutes only for the switch. A WOT switch could likely be rigged up and be more expensive and timely.
 

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NG Autoworks
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All you have to do is rig a switch just like you would on a nitrous install. It's a lot easier. Either mount it by the throttle bracket (for SE's) or under the gas pedal (for SE-R/Spec V). Then it would be a on/off switch that would break the circuit and allow no charge to be drawn off the alternator.
 

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well i know on stangs id you get the pulley kit you have to get a new alternator or you're lights will flicker and die to nothing then get super bright and vise verse
 

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Discussion Starter · #7 ·
NiceGuy said:
All you have to do is rig a switch just like you would on a nitrous install. It's a lot easier. Either mount it by the throttle bracket (for SE's) or under the gas pedal (for SE-R/Spec V). Then it would be a on/off switch that would break the circuit and allow no charge to be drawn off the alternator.
that's what my brain is churning right now :p but reality takes a hold and I think i'd wait on this until I get a new daily driver and this becomes a track day only car

Tony I : A regular switch would be fine for a drag strip but hellacious on a road course!
 

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It's all about load on that belt.
 

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Dine Racer
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Wouldn't you lose power tho?

Trying to run your ignition system at WOT with just 12Volts compared to the 14.? Volts
your car would have. /the higher the power supply, make a better spark.
 

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Discussion Starter · #11 ·
It should be fine. A lot of race teams run w/o alternators if the race is short enough (like a 50 minute sprint race)

I'm not sure about the 12V 14V thing...that sounds familiar but I'm not sure about car audio stuff. I always found it strange that car audio amps were rated for 14 V but the battery is only 12V :p


dakewlndn said:
Wouldn't you lose power tho?

Trying to run your ignition system at WOT with just 12Volts compared to the 14.? Volts
your car would have. /the higher the power supply, make a better spark.
 

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El Greco
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lawngn0mex said:
It's all about load on that belt.
But the Alt pulley will still spin, along w/ the internals of the alternator, right? I mean, the alt. makes volts according to rmps and not the oposite (meaning, if there is no load (alt off w/ switch) pulley and internals will still spin at the same speed, so how do you gain HP?)

Correct me if I am wrong
 

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NG Autoworks
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evangelos K said:
But the Alt pulley will still spin, along w/ the internals of the alternator, right? I mean, the alt. makes volts according to rmps and not the oposite (meaning, if there is no load (alt off w/ switch) pulley and internals will still spin at the same speed, so how do you gain HP?)

Correct me if I am wrong
You are wrong. :)

There have been people that have recorded horsepower loss on the dyno from various loads on the electrical system. I believe one person with an SR20 recorded up to a 6 whp loss when the radiator fans came on. A load on the alternator, is just like a load from the air conditioner. Can't you feel it when your A/C comes on? Although the load may not be as much as the A/C.

If the alternator has to work harder, you get your increased load on the crank. You gain power by less reciprocating mass, just like adding a light flywheel or light crank pulley. Try thinking this way. Your A/C pulley still spins, even if the A/C is not on. It's b/c the A/C clutch is not engaged. So the pulley spins freely. When the A/C is on, the clutch engages, and produces a load.

So, next time when you race, think about all those amps, speakers, neons, etc you have robbing you of power.
 

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Discussion Starter · #14 ·
True!

The load on the alternator is governed by a separate wire. If you look int he FSM you can see it.

What happens is there is a wire that goes to the alternator that tells the alternator how much load is needed. When that voltage moves up or down, it increases or decreases the resistance in the alternator which then sends charge down another wire to the battery. So a cutoff switch should take that wire and basically tell the alternator that there is no load. what I'm not sure of if 0V = no load or if it's a high voltage that means no load.

YES DONT DRAG RACE w/ the radio on!
 
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