18volts?

[Compjake 10+ year member]

Okay, I have a quick question;

My car (1978 Chrysler Cordoba) has the stock electrical (except big3) its a 110 amp alt with external voltage regulator. I have a Wal-mart battery installed currently (1000CA/850CCA) and I read around 17-18volts at the HU.

My question is, if I read 17-18 volts with a 12 volt battery then would it be okay to replace the battery with some Kinetik 16volt batteries, perhaps KHC16V?

I'm not sure what I'm going to run for speakers or the HU yet but I'm thinking about 2 PCX2000D's for my sub-stage (probably 4 RE SX's) and a PCX4.360 to run my speakers.

Will I be able to run those 3 amps at my current voltage safely?

Before I buy and install these amps and what not I will be installing a second 110 amp alt and doing a battery bank of 2-4 batteries in the trunk plus the one under the hood.

If it makes things easier; If I have 2 110amp alts at 17-18 volts should I go with 12 or 16 volt batteries and will the amps I chose be able to function on said voltage without being damaged?

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[93dakota 10+ year member]

Fist off how are you measuring your voltage? second is your alt's external regulator set by you? Your car should not be charging to 18 volts(unless there is something that Chrysler tried on this car i have never heard of). You are lucky that you have not fried any thing. If your car is meant for 12volt system if you are getting any more then 15 volts you are hurting things in your car. Cars that have a 16v systems have a separate 12v system for the car's stock electronics. Even most Head Units wont like seeing that much voltage.

 

[Compjake 10+ year member]

I measured it with a DMM on the memory wire at the HU. The voltage regulator has no settings, its the old 2 wire firewall mounted style. Both the voltage regulator and the alt are less than 6 months old and have been tested working 100%. Apart from the HU the only stock electronics are the ignition system and light bulbs/gauges

The car was made in 1978 and the "Lean Burn Computer" was removed long ago.

 

[I Like Waffle]

lol, are you using the meter right? Could be something wrong with the alt. I metered my brothers car which is a '68 and it was getting 15.3 volts at the amp IIRC, and i know i have a good DMM. Maybe its an old car thing //content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

 

[Compjake 10+ year member]

lol yes, I set it for 12v DC and put pos to pos and neg to neg. not much more to it than that lol

 

[terra 5,000+ posts]

Measure at the batt not the memory wire.

 

[Compjake 10+ year member]

I will have to do that.. but, wouldn't it be higher at the battery vs at the HU because the difference in resistance?

 

[terra 5,000+ posts]

I will have to do that.. but, wouldn't it be higher at the battery vs at the HU because the difference in resistance?

No I think your measurement at the HU was faulty. The battery is the better test. If it is a 12v battery and it measures at 18v when you test it, somethings will shortly be on fire. I think you're first voltage reading was way off. Picture of voltage reading at battery please.

 

[Compjake 10+ year member]

Well when the car is off it reads just under 13 volts at the HU so I'm assuming its correct.. I will test at the battery and I will include a pic.. just give me about an hour.

 

[93dakota 10+ year member]

No I think your measurement at the HU was faulty. The battery is the better test. If it is a 12v battery and it measures at 18v when you test it, somethings will shortly be on fire. I think you're first voltage reading was way off. Picture of voltage reading at battery please.

2x

If you are truly charging your 12v bat with a 18v alternator output you are asking to have your bat blow up or catch on fire.//content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

 

[Compjake 10+ year member]

Okay, last time I checked the voltage it was between 17 and 18 volts.. today on cold or warm start I read 15.70 volts at the battery and my volt meter in my dash (made from old .5 farad cap) read 15.75 volts. Since volt meters on caps are not as "on track" with true voltage I think showing only .05 volts more is close enough to call it the same.





Click the image for larger version if needed. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[jdawg 5,000+ posts]

if you are getting 17-18v you are gonna burn shit up, maybe you have a faulty reg and its charging too high sometimes. Might just wanna swap it out as they are like $20. Cool thing about chrysler cars is they have the external, even in my cars (90 daytona and 90 caravan) a popular mod is to put a old reg like the one you have on the firewall, mine are in the computer but you just unhook the feil wires from the alt and run it to the external reg. Try one of these.

http://www.cpgenerator.com/voltageregulators.html

 

[Compjake 10+ year member]

I'm liking the idea of the stock regulator + adjustable.. going 16volts would be a breeze that way

 

[jdawg 5,000+ posts]

you can get a stock type reg for that car that is adjustable, dont have to run both, just replace the one on the firewall with an adjustable

 

[Compjake 10+ year member]

lol, i should have been more clear.. what you just described is exactly what I meant.