So, I'm researching... and I found out that all the scion alternators have a rated output of about 80 amps..?

I'm looking at buying an xA and I'm just curious to know if I can put in my amp. Does anyone have an idea about how many amps I could expect the car to be using at it's peak? I don't care about the average. I just wanna make sure I'm not going to be blowing the alternator with my amp.

My amp is class d, and it only uses like 26, so what do you guys think?

Thanks ahead of time; I appreciate it.

 

Go get a 2.5 farad power capacitor, and you shouldnt have a problem pushing heavy loads and straining your battery, as well as your alternator.

 

^^exactly, I knew someone who was using way too much power (battery) and the bass would hit or the sub would kick in and his headlights would dim, he got a capacitor and everything was fine....

 

if you are looking at a med to high end system then you should up the alt. i have a 1000d and 75 by 4 amp and a cap and at first it was good but now i am havig problems with my amps not keeping the power. i am looking for a better alt. it just can not keep the power going

 

a cap would help a little, but I would consider getting a deep cycle battery and/or a high output alt. To give some credit to this statement, I am MECP certified installer with American Electronics and have seen numerous people put a cap on a big system without "beefing up" their charging system. A cap is fine, but get the full power from you system, a battery and alt. woould be best. That's just my .02.

 

it was said before. a cap is a band-aid over a bleeder. yeah it will fix the problem short term, but the upgraded alt and battery like installerguy said, will be better.

my $.02

 

I wouldn't reccomend a deep cycle battery unless you are showing your car off a lot with the system on and car off... deep cycle batteries don't like being used at the same time they are being charged... i would reccomend a red top over a yellow top optima or any other non deep cycle type battery...

 

I have heard "the big 3" (upgrading ground wires) would help and would be real cheap/easy to do. Talkin about 10-20$ total. May be something to look into.

 

There is a lot of confusion about this topic but Ohm's Law can help us here. The amount of current demand your system will have on your charging system depends upon the amp and your listening habits.
First lets look at what your vehicle needs to run. Depending on which and how many accessories you are using, you vehicle will need 40 - 60 amps to operate.
Lets say you were planning a 1000 Watt system. Current (amps) = Power (Watts) / Voltage. So lets's plug this into the formula: 1000 Watts/12.5 Volts = 80 Amps.
This is not the whole story however. The number above assumes the amp is 100% efficient, but it's not. In the real world most designs are about 50% efficient when you factor in clipping. This means it will need 2000 Watts to generate 1000 (yikes). So lets see: 2000 Watts/12.5V= 160 amps plus the 40-60 amps you car needs, you need a 200 - 320 amp alternator just to feed your system....or do you?
You are the other factor. Your listening tastes dictate how much of that available power you are going to use with music. Most people will use 20% of the amplifier's power on average with music:
1000*.2=200 Watts (average)
(200*2)/12.5=32amps (average)
If you are like most people, you probably will not need to change the alternator if it's healthy.
Abusive poeple will use 50% of the amplifer's power on average with music:
1000*.5=500 Watts (average)
(500*2)/12.5=80amps (average)
Probably should upgrade.
The major difference between these two types of listeners is the amount of clipping they will drive their systems to. Most people will drive their systems into clipping, some more than others. Clipping dramatically increases average power.
There are other factors that influence average power like Crest Factor of recordings but that is a different discussion.

 

Quick question: If you have the stock HU, and the sub that SCION sells, are you alright? 'Cause that is what I have, no lights dim, but am curious, as I want to add tweeters to the rear, and don't want to strain the system.

 

as far as the battery goes, from personal experience, I'd go with the stinger SP1000 battery. Specs are: Internal resistance 3.1 moohm, 5 second cranking 1200 Amps, SHort circuit current 2600 Amps, 37.8 lbs. EXCELLENT!! Batt dimensions are
6-3/4" H x 7-3/4" W x 6-1/2" D . I have had both red and yellow top batteries, but have found this batt to be better. Just in case anyone cared. Price is in the ball park of $250.00 to $270.00. Oh, the typical life cycles if batt drained is 400 cycles!!

 

The amplifier built into that subwoofer system has little impact on the stock charging system. I am not sure why you would want to add tweeters behind you, but that will not affect the charging system. Adding tweeters to the factory radio could impact the performance of the radio, but the worse that could happen is the chip amplifier inside would overheat under abusive conditions. It most-likely be OK.

 

I want to add tweeters for the folks in the back. But that is going to change, since I talked to my man Gary at KING TOYOTA, and he is going to put in the stereo upgrade speaker package. Tells me this comes with it's own amp. Should make the highs more pronounced in the back. Next Thursday. We'll see. I hope he is right~!

 

i went to look into an alt up grade at the shop where i got my system and they could not find one unless i had it made special which would cost alot more. does someone know where i could find one.

 

I used that same battery for my old Honda and loved it. Funny thing is I went to a Stinger dealer today and he said it's crap. Old Optima dealers say Optimas are crap. Everyone using yellow tops, installers say yellow tops are deep cycle and not good for cars, red top better. Man marketing is a mess.

 

Trust me, you more than likely won't be running near the power that I am, and I am using the stock alternator. You'll be fine.

Kind Regards,
Matt

 

But do you pound away at your system while driving? Just 25% of the wattage you're running could kill an alternator if the music is blaring. I hope not cuz you'd be deaf, or are you? :?

 

Yea, I pound the system sometimes while driving, but not always. Even though I do at times turn it up very loud, it's no where near it's potential as you don't want to be in the car obviously when that happens.

But, I have the battery reserve such that the alternator is not seeing a stress load trying to recharge while it is running. Reserve time is king!

Kind Regards,
Matt

 

where can i get a high output alternator?

 

try ohio generators, or stinger. Also try splmax.com. Ask for Sam Horn, or email him directly at Sam@splmax.com. He helped me greatly for my Alt. Be warned, you'll most likely spend $500+