Voltage Variation Question

[Volvowith18psi 10+ year member]

Hello all, new to the forums!

Had a question about acceptable voltage variations if you don't mind:

Car is a 95 Volvo 850

100 A/H Alt ( Stock )

Optima Yellow Top

"Big 3" Complete w/ 4g

4x BA 5 1/4" off the Kenwood Deck

1x Kendwood 9105D Amp @ 1ohm (900 rms)

1x Kicker 12" L5 in Vented box

After doing my big 3 yesterday, I was monitoring the voltage variations in the lines and had a question about what is acceptable / expected at full "bump" and what I need to be worried about.

Meter read about 14.18ish across the battery w/ the car @ idle, stereo on @ volume 0.

Now, at 95% bump, I was dropping to around 13.7+ - across the battery. The new Alt lead still showed around 14ish.

Is losing around .5v to be expected while the amp and sub are doing their job? Should I be looking into a custom Alt build? Should I be worried my car will not start in a few days/weeks even though the volume is not full most of the time when I drive the car?

I have priced one, from Ohio Gen. @ 525ish for 180-200amp direct bolt on... A bit steep, but meh, Its a Volvo lol. About the only one I can find in the 180 range that's a direct bolt up... Darn the transversely mounted 5cyl engines.

Im also looking at adding a simple 50x4ish kenwood to power my mids and highs to stop the distortion at high volume, would I need to worry about amperage draw then?

Thanks alot for your help!

Andrew

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[n2audio 5,000+ posts]

If the worst you saw was 13.7v you have absolutely nothing to worry about.

You'll probably get more voltage drop out of your pwr window motors.

It isn't uncommon to see voltage sags well into the 12's with no problems to speak of other than minor dimming.

The 9104 was recently tested at less than 700w at 2 ohms, I wouldn't expect much (any) more at 1.

That is not a lot of power for any stock electrical system built in the last several years.

I run 1500w rms (legit) with a 110A alt and only a supplemental 8 gauge from the alt to batt.

 

[Volvowith18psi 10+ year member]

Well, If by several you mean 15 years, then ok.. LOL.. Still have nightmares of my 1st install when I was 16 and burning up 5 Brand new pep boys alts ina week. Don't ask me how I did it, but it happened. Then I forgot to set the battery down in the tray and it arc'd the hood. Ahhh, memory's of little troy banging with flames shooting out from under the hood.

Is minor dimming and flashing of the lights nothing to really worry about then? That's pretty much why I did my big 3 upgrade to stop it, but it didn't help.

( I have day time running lights, so my headlights are always on)

I am interested in the amp testing tho. I had come to believe it was pushing out 900w rms... Hrm...

Ahh, I see.... Its the 9105D not the 9104- Was browsing pictures and noticed the 04 only had 2x 30 amp fuses while mine has 3x...

Thanks alot for the peace of mind!