E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Welcome to the E46Fanatics forums. E46Fanatics is the premiere website for BMW 3 series owners around the world with interactive forums, a geographical enthusiast directory, photo galleries, and technical information for BMW enthusiasts.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Go Back   E46Fanatics > Tuning & Tech > Bavarian Soundwerks' Mobile Electronics Forum

Bavarian Soundwerks' Mobile Electronics Forum
Have all your A/V and electronics questions answered here. Ipods, A/V, Radar Detectors Oh My!
Sponsored by Bavarian Soundwerks

Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 06-14-2013, 08:41 PM   #1
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
Has anyone done the "Big 3" wire replacement?

I'm planning to add a sub in my trunk since my rear deck sub is rattling, (go big or go home right?) but I'm planning to run 1000w to a 12" sub etc. With that much power. I want to replace the the 3 major wires. The battery to alternator, and Alternator to ground. I can't seem to find the route of both of the positive wires (the one from the trunk to front post and front post to Alternator) and the route of the Alternator to ground, since the battery is in the trunk. Any help? Any DIYs out yet?
thanks for looking!
project330ci is offline   Reply With Quote
Ads by Google

Guests, get your FREE E46Fanatics.com membership to remove this ad.
Old 06-14-2013, 09:05 PM   #2
BringsMeWomen
Registered User
 
Join Date: Oct 2012
Location: Calgary, Alberta
Posts: 223
My Ride: 2001 330ci
Has anyone done the "Big 3" wire replacement?

Im looking to do this as well in my coupe. A DIY out there would be nice!


Sent from BimmerApp mobile app
BringsMeWomen is offline   Reply With Quote
Old 06-14-2013, 09:51 PM   #3
bernie21614
Registered User
 
Join Date: Apr 2010
Location: Glendale, AZ
Posts: 326
My Ride: 01 330i
Re: Has anyone done the "Big 3" wire replacement?

the alternator uses the housing itself as the ground. The positive cable runs along the passenger side from the battery to the post in the engine bay, to accesses it you remove the lower plastic trim on the foot step area and remove the pieces underneath the glove box and look behind the carpet.

Last edited by bernie21614; 06-14-2013 at 09:53 PM.
bernie21614 is offline   Reply With Quote
Old 06-15-2013, 04:50 PM   #4
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
anyone know how to do the positive to under the hood post to the alternator?? bump
project330ci is offline   Reply With Quote
Old 06-15-2013, 04:59 PM   #5
bernie21614
Registered User
 
Join Date: Apr 2010
Location: Glendale, AZ
Posts: 326
My Ride: 01 330i
Re: Has anyone done the "Big 3" wire replacement?

I don't know how to do it, but I do know that the cable goes from the post to the starter and then to the alternater. I'm going to be cleaning all my connections here soon and when I do I'll post some pics of how it's routed.
bernie21614 is offline   Reply With Quote
Old 06-15-2013, 05:11 PM   #6
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
ight thanks send me a DIY when you got it. Probably gunna do it withing a week or 2
project330ci is offline   Reply With Quote
Old 06-17-2013, 09:25 PM   #7
braaang
Registered User
 
Join Date: Mar 2013
Location: Back in 'straya
Posts: 196
My Ride: E46 M3
good idea to add another ground wire or go bigger for your ground to battery.
braaang is offline   Reply With Quote
Old 06-18-2013, 12:05 AM   #8
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
Has anyone done the "Big 3" wire replacement?

Quote:
Originally Posted by braaang View Post
good idea to add another ground wire or go bigger for your ground to battery.
That is the last one of the big 3thats easy since the ground is like right there next to the battery


Sent from BimmerApp mobile app
project330ci is offline   Reply With Quote
Old 06-19-2013, 01:44 AM   #9
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
bump?
project330ci is offline   Reply With Quote
Old 06-20-2013, 07:31 PM   #10
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
anybody?
project330ci is offline   Reply With Quote
Old 06-25-2013, 11:21 PM   #11
bernie21614
Registered User
 
Join Date: Apr 2010
Location: Glendale, AZ
Posts: 326
My Ride: 01 330i
Re: Has anyone done the "Big 3" wire replacement?

I started cleaning up some connections and testing everything, I have some pics of the power wires however they are cell pics and my phone takes horrible pictures, I'll post them up tomorrow
bernie21614 is offline   Reply With Quote
Old 06-25-2013, 11:59 PM   #12
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
Quote:
Originally Posted by bernie21614 View Post
I started cleaning up some connections and testing everything, I have some pics of the power wires however they are cell pics and my phone takes horrible pictures, I'll post them up tomorrow
any general idea of where they are routed will help, thanks!
project330ci is offline   Reply With Quote
Old 06-26-2013, 07:42 PM   #13
Moosecakes
Registered User
 
Join Date: Nov 2010
Location: Oregon
Posts: 836
My Ride: 02' SMG M3
I'm kinda confused as to what your asking for.. and why you need it.. why not just go out to your car and trace each wire and figure out where it goes? It's not like your adding more things to the system just upgrading wiring.. and 1k watts is ****ing absurd... you don't need that much. Ohm your sub and amp down to 1 if it's stable and run a 400w amp, I ran 2 10" orion HP's with a 400w boston audio amp at 1ohm and I hit 148db.. that was absolutely stupid loud.

And also, upgrading to a thicker gauge wire is not going to help you if you are concerned about getting proper power. You need to have your alt. rebuilt for higher output along with the larger wiring.

Honestly nothing bigger than 2g is necessary for most typical stereo installs. I'm only running 4g for my amp power and ground.

Have you seen how thick the factory battery cable is? Fawking huge. You'd also need an inline breaker for the power wire for safety.
__________________

Last edited by Moosecakes; 06-26-2013 at 07:42 PM.
Moosecakes is offline   Reply With Quote
Old 06-27-2013, 01:00 AM   #14
bernie21614
Registered User
 
Join Date: Apr 2010
Location: Glendale, AZ
Posts: 326
My Ride: 01 330i
The power cable goes through the passenger side, one cable goes to the fuse Panel and attaches to a power buss and the other goes to the passenger footwell area where it attaches to another cable which then goes to the engine hood post. I,m going to go ahead and finish cleaning up the connections sometime this week, but in the mean time here you go.
Attached Thumbnails
Click image for larger version

Name:	IMG_20130625_171307.jpg
Views:	69
Size:	97.8 KB
ID:	513284   Click image for larger version

Name:	IMG_20130625_171314.jpg
Views:	68
Size:	133.1 KB
ID:	513285   Click image for larger version

Name:	IMG_20130625_172332.jpg
Views:	67
Size:	124.2 KB
ID:	513286   Click image for larger version

Name:	IMG_20130625_174018.jpg
Views:	67
Size:	66.8 KB
ID:	513287  

Click image for larger version

Name:	IMG_20130625_175513.jpg
Views:	59
Size:	120.6 KB
ID:	513288   Click image for larger version

Name:	IMG_20130625_184028.jpg
Views:	62
Size:	111.4 KB
ID:	513289  
bernie21614 is offline   Reply With Quote
Old 06-27-2013, 01:03 AM   #15
bernie21614
Registered User
 
Join Date: Apr 2010
Location: Glendale, AZ
Posts: 326
My Ride: 01 330i
One more of the hood post cable with the back cover removed
Attached Thumbnails
Click image for larger version

Name:	IMG_20130625_165145.jpg
Views:	54
Size:	86.7 KB
ID:	513290  
bernie21614 is offline   Reply With Quote
Old 06-27-2013, 01:38 AM   #16
mkodama
Registered User
 
mkodama's Avatar
 
Join Date: Oct 2006
Posts: 33,171
1000 Watts / 12 Volts = ~83 Amps

Your starter uses 3 times that current, so your wiring is already able to handle the current draw from your sound system, and BMW did their math to get the wiring size correct.

Your limitation is going to be how much power your alternator can provide and the capacity of your battery. If your car's power system can't provide as much power as the sound system wants to consume, the entire system voltage is going to drop and you'll see your lights flicker. This isn't very good for the car's electronics or your music. You can either get a larger alternator so that the car can provide enough power, or you can add more battery capacity to fill in during the times your alternator can't provide enough power.
__________________

mkodama is offline   Reply With Quote
Old 06-27-2013, 01:41 AM   #17
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
Quote:
Originally Posted by Moosecakes View Post
I'm kinda confused as to what your asking for.. and why you need it.. why not just go out to your car and trace each wire and figure out where it goes? It's not like your adding more things to the system just upgrading wiring.. and 1k watts is ****ing absurd... you don't need that much. Ohm your sub and amp down to 1 if it's stable and run a 400w amp, I ran 2 10" orion HP's with a 400w boston audio amp at 1ohm and I hit 148db.. that was absolutely stupid loud.

And also, upgrading to a thicker gauge wire is not going to help you if you are concerned about getting proper power. You need to have your alt. rebuilt for higher output along with the larger wiring.

Honestly nothing bigger than 2g is necessary for most typical stereo installs. I'm only running 4g for my amp power and ground.

Have you seen how thick the factory battery cable is? Fawking huge. You'd also need an inline breaker for the power wire for safety.
LOL anything else you dont want to tell me thats pretty obvious? 1. If I can get resources online that could help me already on how to find out what I need, why should I spend time under my hood looking for it? I only need to find out so I can roughly buy as much wire as I need to do the job. and 1K watts? and you dont know my sub/amp set up. its stable at 2 ohms. so theres that. and unlike your thinking. im not in it to blow out my ears and break windows. Im using quality and over power just so i know i wont be tiring out my subs/amp running it at its max 24/7. its not just about quantity. its clarity. and why not 0 gauge? its better for the car to over size if anything. plus 2 gauge isnt common. 0 is. better current flow. which is needed. So i dont know why, you would spend your time explaining your setup to me not knowing if i already had one, or my future plans of my sound system. But ey we all make mistakes. so there you go oh btw. the inline fuse is just a dead giveaway for anyone running an amp. anyone else want to explain to me something that wont help my situation?
project330ci is offline   Reply With Quote
Old 06-27-2013, 01:48 AM   #18
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
Quote:
Originally Posted by mkodama View Post
1000 Watts / 12 Volts = ~83 Amps

Your starter uses 3 times that current, so your wiring is already able to handle the current draw from your sound system, and BMW did their math to get the wiring size correct.

Your limitation is going to be how much power your alternator can provide and the capacity of your battery. If your car's power system can't provide as much power as the sound system wants to consume, the entire system voltage is going to drop and you'll see your lights flicker. This isn't very good for the car's electronics or your music. You can either get a larger alternator so that the car can provide enough power, or you can add more battery capacity to fill in during the times your alternator can't provide enough power.
thanks for the tips! I am thinking about the alt. but i just got a fresh battery thats better than the original i had for a while so with the current power draw issue. if it does so pull too much, i will invest in a alternator. but i also have a kill switch for my amp so it wont be running 24/7 when the car is on. it may help. but down the road if my alt really cant handle it. i will invest in an alt. or ill just go down in amp watts.
p.s. my alt is still oem so it may just be time to rebuild/replace. so i might as well go with a better alt.
project330ci is offline   Reply With Quote
Old 06-27-2013, 01:52 AM   #19
project330ci
Registered User
 
Join Date: Jun 2011
Location: SoCal909, CA
Posts: 72
My Ride: steel grey 02 325ci
Quote:
Originally Posted by bernie21614 View Post
The power cable goes through the passenger side, one cable goes to the fuse Panel and attaches to a power buss and the other goes to the passenger footwell area where it attaches to another cable which then goes to the engine hood post. I,m going to go ahead and finish cleaning up the connections sometime this week, but in the mean time here you go.
thanks a lot! thisll help me forsure
project330ci is offline   Reply With Quote
Old 06-27-2013, 02:06 AM   #20
mkodama
Registered User
 
mkodama's Avatar
 
Join Date: Oct 2006
Posts: 33,171
Quote:
Originally Posted by project330ci View Post
thanks for the tips! I am thinking about the alt. but i just got a fresh battery thats better than the original i had for a while so with the current power draw issue. if it does so pull too much, i will invest in a alternator. but i also have a kill switch for my amp so it wont be running 24/7 when the car is on. it may help. but down the road if my alt really cant handle it. i will invest in an alt. or ill just go down in amp watts.
p.s. my alt is still oem so it may just be time to rebuild/replace. so i might as well go with a better alt.
No need for a kill switch, just turn down your volume. 1000 watts is only with the sub turned all the way up, which will likely be painful and nauseating at that point. Just install the amp and sub for starts, set it up properly, and then see how your system handles it.
__________________

mkodama is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Censor is ON





All times are GMT -5. The time now is 11:55 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
(c) 1999 - 2011 performanceIX Inc - privacy policy - terms of use