Headlights still dimming with 270a alternator

[Athecal]

So I put a 270a brand x alternator in my truck a while back when the alternator needed replaced. This build I have been working on slow trying to do things the right way all the way for once. Already had 1/0 upgrades to the big 3, plus extra grounds. Couple weeks ago I ordered 2 Stereo Integrity SQL 12s and a DD-1+ built an enclosure and hooked them up to my NVX 1700w monoblock. I initially set the gains just underneath the point of the distortion light coming on on the DD-1+ and let them stay like that for a few weeks then I reset my amp gains with a 6db overlap and every time the beat hits I get headlight dimming and voltage drop. 

 

Is it the lead acid battery under the hood? 

Do I need to upgrade that battery, or add a second battery? What is the proper fix for this?

[Wifebtr]

Maybe the battery can't supply the current demand when the bass hits hard.

 

Your alt can charge up batteries quick but the battery might need to be upgraded. 

 

What make and model truck? Does it have that feature like Hondas where it limits alt output to increase fuel economy?

[Chaski]

Have you had your battery load tested?  Do you know what the CCA / group size is?

[MrSkippyJ]

regular halogen headlights? they dont have any kind of voltage regulation so any changes in voltage will dim/brighten them. Even a high output alt will lag behind current demands. So it is perfectly normal to see diming even with a HO alt. You can either just ignore it or get some voltage regulated lights.

[jgi420]

Well it could be quite possible  the alternator isn't putting out the voltage you think it's putting out if it's a cheaper alternator now this hasn't been confirmed because I have the same problem now almost anybody that I've talked to before when they were putting out massive amounts of power they had the typical headlight dimming but usually  seen on an alternator that is reaching its capacity you could try using an AGM battery but there's no guarantee the dimming is going to go away. 

[Barry Frasier]

On 12/11/2022 at 7:41 AM, Athecal said:

So I put a 270a brand x alternator in my truck a while back when the alternator needed replaced. This build I have been working on slow trying to do things the right way all the way for once. Already had 1/0 upgrades to the big 3, plus extra grounds. Couple weeks ago I ordered 2 Stereo Integrity SQL 12s and a DD-1+ built an enclosure and hooked them up to my NVX 1700w monoblock. I initially set the gains just underneath the point of the distortion light coming on on the DD-1+ and let them stay like that for a few weeks then I reset my amp gains with a 6db overlap and every time the beat hits I get headlight dimming and voltage drop. 

 

Is it the lead acid battery under the hood? 

Do I need to upgrade that battery, or add a second battery? What is the proper fix for this?

where are you grounded at?ive got a d4s jp 43 pushing a fi Neo 18 at 1 ohm and my grounds are from the frame directly the dust blocks,22 inches long,ive got a limitless retro 30 running the whole truck and the amp is set to 65 volts which I believe us right at 4500 watts, at idle pushing hardly get no dimming and no clipping,im thinking it is your ground connections, but I could be wrongly alt is a stock 200 amp in a 2016 f150 xlt

 

[jgi420]

Based on what you're saying that doesn't seem like it's RMS power you're talking about you must be talking about 4,500 Watts Peak

[jgi420]

2 hours ago, Barry Frasier said:

where are you grounded at?ive got a d4s jp 43 pushing a fi Neo 18 at 1 ohm and my grounds are from the frame directly the dust blocks,22 inches long,ive got a limitless retro 30 running the whole truck and the amp is set to 65 volts which I believe us right at 4500 watts, at idle pushing hardly get no dimming and no clipping,im thinking it is your ground connections, but I could be wrongly alt is a stock 200 amp in a 2016 f150 xlt

 

 

2 hours ago, Barry Frasier said:

where are you grounded at?ive got a d4s jp 43 pushing a fi Neo 18 at 1 ohm and my grounds are from the frame directly the dust blocks,22 inches long,ive got a limitless retro 30 running the whole truck and the amp is set to 65 volts which I believe us right at 4500 watts, at idle pushing hardly get no dimming and no clipping,im thinking it is your ground connections, but I could be wrongly alt is a stock 200 amp in a 2016 f150 xlt

 

Based on what you're saying it sounds like you're talking about 4,500 Watts Peak that can't be RMS

[SnowDrifter]

On 12/13/2022 at 7:19 AM, MrSkippyJ said:

regular halogen headlights? they dont have any kind of voltage regulation so any changes in voltage will dim/brighten them. Even a high output alt will lag behind current demands. So it is perfectly normal to see diming even with a HO alt. You can either just ignore it or get some voltage regulated lights.

This.

Anything else about equipment is largely irrelevant.

Alts won't stop the millisecond level voltage dips and spikes. nor will a bank of batteries

Need led / hids, 2 charging systems, or a voltage regulator/driver for the headlights

Just.... If you go the hid/led route, at a minimum, get bulbs that will let  you adjust the focal point so you don't have squirrel finders. Or better yet, convert the things to projectors from the retrofit source or something (there are others out there, those are just the only ones that pop into my head).

[Barry Frasier]

19 hours ago, jgi420 said:

 

Based on what you're saying it sounds like you're talking about 4,500 Watts Peak that can't be RMS

yes sir,,my brain injury doesn't always let me say what im want to spell out