loosing a half of volt

[Rashaddd 5,000+ posts]

Do you have a pos and neg wire going directly from your amp to the back bat?

There really shouldn't be any delta between them hardly at all, putting your dmm on ur amps terminals is almost like putting it right on the short wires coming from your battery, which is almost like putting the dmm right on the battery terminals

There might be like a .05-.1 drop max but...shouldn't be that much, unless of course those wires are long or bad connection etc...

 

[MmatsDude 10+ year member]

The probable reason connecting a negative to the chassis may help is because your single line of 1/0 negative would be choaking and the chassis helps 'share' the negative run. The chassis is not a better conductor than an OFC 1/0 wire.
You may also try adding a 1/0 negative directly from alt to front battery (not using the engine block). I had a voltage increase when I did this from 12.7 to 13.2 when I connected my rear 1/0 negative directly to my alt, which has a grounding bolt on the alt chassis. Running yours from alt to front battery would do the same thing since you already have a 1/0 negative going to the rear at your front battery. But you could always test to see if moving the rear negative line directly to the alt improves voltage.

In my case the weak point was my negative from alt to front battery, which is going through my engine block to battery and chassis both with 1/0. When I connected my amps negative run directly to my alt I saw the big increase. But this may be due to the HO alt I have and wouldn't help as much on a system with a lower amperage alternator.

We have about the same wattage, too. I'm running 1900RMS total with a 180a Excessive Amperage alt and 1 Kinetik HC1400 up front.

Can you take pics of that? I whan't to see how you did it.

 

[jrwalte 10+ year member]

The wire on the top of the alt is the negative.

I plan on running another 1/0 from that same bolt to the front battery but haven't gotten around to it yet.

 

[DBBOOM 10+ year member]

Why red flex on the ground and black flex on the positive?

 

[x2o 10+ year member]

Why red flex on the ground and black flex on the positive?

To confuse anyone who wants to work on it? Haha, I'd be pretty //content.invisioncic.com/y282845/emoticons/verymad.gif.3f39c5c2fd57527b671fad3efdfac756.gif if I were working on that. I've come to assume bright colors and positive and dark colors as neg. //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif. I hate when people want me to do something on their car and they have rainbows of wires //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif. It's DMM time when that happens.

 

[DBBOOM 10+ year member]

Just asking, seems odd to me too.

 

[jrwalte 10+ year member]

The dark flex is the factory wire. I used red just because it was left over from my 1/0 positive run. So I have my positive and negative 1/0 runs in red. Only an idiot working on the car wouldn't know which is which //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[x2o 10+ year member]

The dark flex is the factory wire. I used red just because it was left over from my 1/0 positive run. So I have my positive and negative 1/0 runs in red. Only an idiot working on the car wouldn't know which is which //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Haha obviously, I was joking //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif.

Only time it's a problem is when it's in the cabin, if your just touching engine wires you can easily follow them back. Although I've heard of some sneaky wiring that goes through dash's and whatnot then pops back out a magic grommet in the engine, making it that much harder. //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

I love working on cars and not knowing what I'm doing all the way though, keeps things interesting! //content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif

 

[knukonceptz 10+ year member]

Any fuses inline? Those will account for some loss

 

[king ranch 5,000+ posts]

one inline upfront by the battery and one in the back by the back battery and another between the amp and the back battery

 

[jdawg 5,000+ posts]

Can you take pics of that? I whan't to see how you did it.

You may also try adding a 1/0 negative directly from alt to front battery (not using the engine block). I had a voltage increase when I did this from 12.7 to 13.2 when I connected my rear 1/0 negative directly to my alt, which has a grounding bolt on the alt chassis

alot of cars have this factory, mine does, and if its there then why not upgrade, also if there isnt one stock how well do you think the alt grounds through alt brackets? Alot fo cars have multiple brackets, bushings, tiny bolts, etc May not help in all cases but if you can do it the why not? If yor alt doesnt have an extra bolt then take out a bolt where the case bolts on, slide a ring in then put the bolt back in. Just needs to attach to the case.

 

[king ranch 5,000+ posts]

alot of cars have this factory, mine does, and if its there then why not upgrade, also if there isnt one stock how well do you think the alt grounds through alt brackets? Alot fo cars have multiple brackets, bushings, tiny bolts, etc May not help in all cases but if you can do it the why not? If yor alt doesnt have an extra bolt then take out a bolt where the case bolts on, slide a ring in then put the bolt back in. Just needs to attach to the case.

so you attatch a piece of 1/0 wire from your engine to your alt casing or a bolt that holds the alt to the engine or use a bolt on the alt itself and wire it to the engine

 

[jdawg 5,000+ posts]

I would wire it to the frame, you should already have a better block to frame ground but if it isnt too hard i would do alt to frame. On my one car it is factory alt to frame

 

[jdawg 5,000+ posts]

dbl post

 

[MmatsDude 10+ year member]

The wire on the top of the alt is the negative.
I plan on running another 1/0 from that same bolt to the front battery but haven't gotten around to it yet.

nice man im going to try to do one like that, so you have that ground to your battery right?