Bigger Alternator for Protege

[MP5stephen]

I'm having voltage drops in my electrical system in my car, and I need more power. I'm sort of running a lot of electronics off 2 batteries. One battery is in my engine bay(obv), the other is in the hatch. I have 1 amp(bass amp) running off both batteries, and a second amp running off of the second battery(Kinetik HC800). I have done the big 3 circuit in the bay already, and that helped, but minimal. I am planning to eventually replace one of my amps with a 2000w amp running off both batteries, and that'll require more power.

My question is, are there different alternators that produce more power for Mazda that I could swap from a different Mazda? Do the 626 and Millenia alternators crank out more(there's a bunch at the junkyard)?

P.S. I'm not looking to spend $300-$500 on a new aftermarket alternator.

Thanks

 

[Focus]

I bought my 140A one from Maniac Electric Motors $188

 

[Tzar177]

I bought my 140A one from Maniac Electric Motors $188

Direct swap? Got a part number?

 

[Focus]

Direct swap? Got a part number?

http://www.maniacelectricmotors.com/140amphioual4.html

 

[AusOrion]

I read the description of the item and also the comments underneath as well. Looks like a very nice product.

Focus, did upgrade the main alternator power cable? If so, did you do this as a precautionary measure or do you consider it a 'must do'?

 

[pw~mp5]

I would say it is a must. The size of the cable determines how much current it can safely carry. If your cable is undersized the cable will get hot and potentially pose a fire hazard. They have a simple chart suggesting the cable size vs current. http://www.maniacelectricmotors.com/powercablekits.html

 

[CheeseHelmet]

I would say it is a must. The size of the cable determines how much current it can safely carry. If your cable is undersized the cable will get hot and potentially pose a fire hazard. They have a simple chart suggesting the cable size vs current. http://www.maniacelectricmotors.com/powercablekits.html

Besides the safety concern, if the cable is too thin you can get a considerable voltage drop across it. That wasted power is dissipated as heat, which causes the resistance of the wire to increase which increases the voltage drop (until something catches fire ).

It would be a waste of money to upgrade the alternator and not upgrade the wiring (don't forget the grounds!).

 

[Focus]

What they said ^

 

[XJ^remy]

sweet thread(2thumbs).....good to see good electrical advice being passed on

most dont realize the potential of up-amping the system (alternator, mains, & circuit protection....wiring is equally important) rather than going to a 2nd battery....but for the OP, if you end up going w/140A + 2 batteries, you'll have more than adequate electrical potential

best thing to do, is figure out the voltage drop of the system....its a bit involved, & may be easier with a 2nd set of hands....but IMO, its essential to kno where/if there's faulty wiring, devices, & MP5Stephen's, case to alleviate the dimming lights & malnourished electronics

all devices, wire, & length of wire will all give current (measured in amps) resistance (measured in ohm's)...here's a good how to on voltage drop i just quickly looked up....http://www.engine-light-help.com/voltage-drop.html

for added electronics (audio amps, aux lights, tv's, navigation, etc.) its important to know how much amperage its gonna draw....VoltAmps (or Watts)/Volts = Amperage

automotive volts is obviously 12, watts will be defined on the device (i.e. 200W Audio amp, etc.)....divide those numbers gives you the total wattage the device requires to operate efficiently & correctly.....total wattage can be added together to give you a total

there are a lot of factors to think about in an electrical system....it takes time, testing, math, some more time, & knowledge on how to make it all work, correctly, & most importantly, safely......one analogy that i was taught, just stuck with me....think electricity in a circuit like water flow in a pipe or hose.....amperage is the measure of flowing electrons (current), voltage would be the amount of force on each electron, supplied by the battery (for the analogy, a water pump).....a gallon/min just dribbles out of a low pressure system, but restricting flow (spray nozzle, kinking, or finger over the end) will maximize the force of the water as the pressure has increased....this is in essence, the act of a installing a HO alternator to get more wattage out the supplied voltage.....they key here is also LARGER MAINS, so the pressure doesnt rip apart the hose & destroy your flowers

hope this rant helps & X2 on the alternator options for the P5.....i'd also love to kno if there are any OEM options that'll swap??

 

[MP5stephen]

Yes, thank you for the help and links.
When you talk about replacing the cables, you mean the stock cable from alternator to fusebox, or cables that charge the battery? I've done the circuit wiring with the alternator. one engine ground, one chassis ground. All my battery(+) and grounds(-) are with 4awg wire with upgraded main battery terminals. I have a main fuse rated at 100a, which might be too small? Should I get a bigger fuse rated for 150a? So a 140 alternator would be a good size to keep ample power with minimal voltage drop?

 

[XJ^remy]

no problem, glad to help tho i'm not 100% specifically on the P5 charging system wiring (researching as we speak, hence how i came across this thread)

I've got a 98 cherokee that I upgraded with a 136A alternator, 1AWG cables, & 150A fuse....B+ to Power Distribution Center, B+ to starter, Alternator output to PDC, B- to fender, engine block, firewall

So when Im talkin cables, its charging, alternator to circuitry, & just as important, grounds.....& yea get a 150A fuse, so you're using all of the alternators potential, yet protecting the circuitry & components from a spike/draw higher than 150A...you can use 100A, but with the essentials (start up, lights, wipers, heat/cooling....if u draw more, like 2 high wattage amps for speakers & subs would, the fuse will blow)....the 140A alternator want to supply the higher demand, but the fuse wont

as far as it being enough, you've gotta do the math.....take into account what your electronics draw, how often they're used, in conjunction with other electronics

 

[spicyprotevo]

So when Im talkin cables, its charging, alternator to circuitry, & just as important, grounds.....& yea get a 150A fuse, so you're using all of the alternators potential, yet protecting the circuitry & components from a spike/draw higher than 150A...you can use 100A, but with the essentials (start up, lights, wipers, heat/cooling....if u draw more, like 2 high wattage amps for speakers & subs would, the fuse will blow)....the 140A alternator want to supply the higher demand, but the fuse wont

as far as it being enough, you've gotta do the math.....take into account what your electronics draw, how often they're used, in conjunction with other electronics

i believe this would be true if you REPLACED your current wires with larger ones. but if we were to do as Maniac Electric Motors says and use a second wire IN ADDITION to the stock one, we would only need say..100A fuse.

 

[Tzar177]

So, what fuse would you use if you are going to use ONLY the upgraded power cable?

 

[CheeseHelmet]

So, what fuse would you use if you are going to use ONLY the upgraded power cable?

150A. I hope you also plan to replace the grounds as well.

 

[Tzar177]

150A. I hope you also plan to replace the grounds as well.

150A? Thought it had to be lower than what the alternator is rated for? Engine grounds? I already have a 10 point 4awg grounding chain

 

[CheeseHelmet]

150A? Thought it had to be lower than what the alternator is rated for? Engine grounds? I already have a 10 point 4awg grounding chain

Oops, for whatever reason I thought that alternator put out more than 150A.

Go with 100A or maybe a little higher. You want a bit of headroom to make sure that if you have a short the fuse will actually pop.

 

[Protg 5 guy]

I bought a 160 amp alternator from powermax usa for $186. Does anyone know the wire lengths I need to do the big 3 on a 02 protege5