Adding ground wires under the hood

[Dan_]

I know a few people who own Subarus. I've been reading about adding ground wires to various places under the hood as an aid in engine run ability.

 

I've been thinking about this and have a few thoughts and questions.

 

How old are these cars that should have this modification?

 

Having worked on a Dodge Dakota that had factory wire splices fail and cause a no-start situation. I'm wondering if there is a ground that could be repaired and not adding all of the ground wires?

 

I see wires going to the strut towers, the core support and to the engine block. Is the factory grounding that poor that all of these connections are required? I just don't see this happening without something damaging the factory wiring.

 

Thanks for your insight!

 

Dan_

[Flying Anvil]

I'm with you on this and would like hear more about this. I have found in the past, more wire,moving parts ect, more problems or more things to go wrong or break. I do understand the importance of a good reliable ground but, why so many? Is this more of an off road deal? Why ground to the shock towers?

I am a practicing "less is best", "KISS"= Keep It Simple Stupid, "SWAG" method= Scientific Wild Ass Guess and "The EYE don't Lie" theorems.

[WESTcoast]

from what I read and experienced is that when with cars our age like you said things vibrate and shake apart. The ground connections could get loose, rust, age, causing weaker connectivity between the negative and the battery.

 

Having more grounds is always a good thing in keeping a reliable connection. Think of it as for your cellphone with multiple connections to different towers gives it better signal right? Same principal goes for hard worked cars such as regular 15 year old cars you see on the daily.

 

Any car that's been through a full rebuild such as show cars, track cars really dont have a grounding kit such as ones you will find. Since thier rebuild is quite newer, and instalations alot cleaner,wires are more kept maintianed and most likely new. No rust on connections, paint is clearing removed for strongest connection.

 

All in all if you are looking for one for the legacy with instructions on where to attach it to here you go

 

http://www.paranoidfabrications.com/shop/the-legacy-lucid-grounding-kit/

[Dan_]

from what I read and experienced is that when with cars our age like you said things vibrate and shake apart. The ground connections could get loose, rust, age, causing weaker connectivity between the negative and the battery.

 

Having more grounds is always a good thing in keeping a reliable connection. Think of it as for your cellphone with multiple connections to different towers gives it better signal right? Same principal goes for hard worked cars such as regular 15 year old cars you see on the daily.

 

Any car that's been through a full rebuild such as show cars, track cars really dont have a grounding kit such as ones you will find. Since thier rebuild is quite newer, and instalations alot cleaner,wires are more kept maintianed and most likely new. No rust on connections, paint is clearing removed for strongest connection.

 

All in all if you are looking for one for the legacy with instructions on where to attach it to here you go

 

http://www.paranoidfabrications.com/shop/the-legacy-lucid-grounding-kit/

 

I believe a cel phone can only connect to one tower at a time.

 

I don't own a Subaru so I don't have one to do any testing.

 

Who has done these grounding mods? Have you removed the wires from the battery and taken a multimeter, and checked for current from the grounding points and the battery ground? If grounding is deficient in the area the ground wire is, there should be a measurable amount of current.

 

I am aware that the engine runs a lot better with an adequate power supply. If the supply is inadequate, find the reason why. Has a factory wire splice failed? Look into the wiring schematics, trace the wires. Fix the problem.

[WESTcoast]

Yes a cellphone connects to one tower at a time, but having multiple cellphone towers helps contribute to a solid, reliable connection. That's what I meant by the cellphone thing.

 

I have installed a grounding kit on a friend's 2.5rs and from what we noticed was the the didn't dim as much with with audio setup as it use to and the car had a better idle. I don't have a multimeter to test, nor do I think these grounding kits are going to be big improvements. If anything, it's adding a bit of reliability and another mod to your parts list

[twisty]

 

Who has done these grounding mods? Have you removed the wires from the battery and taken a multimeter, and checked for current from the grounding points and the battery ground? If grounding is deficient in the area the ground wire is, there should be a measurable amount of current.

 

 

i did the ground mod to my leggo wagon a while ago. first i ohmed out the ground points for a week or so to get a baseline reading when hot and cool. it was pretty much the same across the board, and usually ran at about 2.5 or so. i put one strap on and ran it like that for a while to see what the rating would change to, and to that point it dropped to about 1.7. i put the other 4 on and let it run like that, my ground circuit to the engine and other points is about .4 most of the time. other times ive seen it go to .7 and .2, but im thinking that may be the meter/ my hand/ dirt. while the circuit definitely did get less resistance, i didnt see much in the way of "performance" or anything. it seems to idle a bit smoother with the AC on, and that was really the goal i was looking for anyway. could all be in my head tho.

 

whether this would be a good maintenance item for other cars? no idea. i guess you could test your grounding circuits and see how much resistance there is, see if there is room for improvement. but, just like with the subarus, youd have to be able to quantify the lack of grounding to the ECU, not just to the block/ towers/ wherever.

 

and no, cell phones reside on two towers at a time when handing off. otherwise your call would be dropped when changing over.

[stevenva]

An easy way to do this mod (AKA Big 3) Is just add onto, you don't have to replace, the grounds with much beefier cable. While your at it you should add onto the positive cables as well with the same gauge cable that you used on the grounds. The first time I did this I used 4GA car stereo power wire. It was kinda pricy for what you get. This last time I used 2/0GA welders cable. I love working with that stuff so much that I'll never buy regular car stereo stuff again. It's cheaper, more flexible, has much finer copper strands and it's abrasion, oil and gas resistant. I've gotten some funny reactions when people see the thick cable emblazoned with the words "Welders Cable". It's perfect for this application.

[rdleg05]

There have been several grounding mods done. see this thread from NASIOC: http://forums.nasioc.com/forums/showthread.php?t=674153&highlight=grounding+mod

 

Although this is geared for an Impresa/WRX, it can still be used for a Legacy and the grounding points match.

 

I did this to my 02 WRX and found that idle was smoother and there was a lack of hesitation under acceleration. I will be doing this same mod on my newly acquired 97 black Legacy 2.5 GT sedan......

 

cheers

 

rdleg05

[JJay03]

Has anyone made their own kit? I think I might make my own just need to decide on what wire I want to use and what ends.

[harrumphicus]

I saw a thread about this a month or so ago - I think the OP was using 8g speaker wire for his grounding kit DIY.

[JJay03]

I think I found the wire and terminals I want to use just trying to decide how I want to run the wires now I dont want clutter. Ide still like to replace the original battery cables im sure they are corroded since they are just crimped on and not soldered.