Vetteran'81

As I am working through the electrical system on my '81, I am running into mysteries here and there.

The latest is a heavy gage ground wire bolted to my manifold that runs back and under all the way to the rear chassis where the battery ground is bolted. Since this is a non-stock engine setup (350 w/Canfield heads, Edelbrock aluminum intake, etc) is there some logic to having this ground wire attached? It has some real issues with bubba splices, etc but seems to just be a straight run for ground. If its not needed I'd like to remove it. Otherwise, I'll need to run a new one because of the crappy splice/repair attempts. (The red part is an 8" piece of wire spliced in to 'repair' the ground wire.)

CoolShark

Looks like a grounding wire from the engine to the frame. Definitely not the stock way of doing a ground strap.

Vetteran'81

Thanks Coolshark. Any suggestions for a more "stock" way of doing it? I would really like to get rid of this nasty looking thing...

bluthundr

Something like this, from engine to frame - http://www.napaonline.com/Search/Det...119_0006398824

mds3013

Cut existing wire to length, add crimped and soldered eyelet on end and bolt to motor mount bolt in side of block. Route wire to clear exhaust. mike...

Vetteran'81

Mike, could you expand on that a little? One end is bolted to the motor mount bolt and the other goes where?

I have the AIM, but am not sure how to adapt the diagrams to my particular situation.

mds3013

I was describing how you could do it without changing the end under the car. Mainly to get the end pictured off the upper side of the engine. Here is the stock set up on my '77. Pass. side pictured. mike...

TimAT

Just like that with star lockwashers under the bolt heads.

DRIVESHAFT

That wire originally grounded to the back of your alternator

Vetteran'81

Man, this is great info! Thanks folks.

That is one huge looking ground wire. The ground straps I got at O'Reilly looks tiny in comparison.

CA-Legal-Vette

Remember that the ground has to carry essentially the same current to the starter as the power wire from the battery, though not as far so doesn't have to be quite the same diameter. If the ground that you showed was the only one then it would have fried every time you start the car. You may have a larger ground at the front of the engine (where mine is). There are also a number of possible paths to the frame including the coolant through the rad, exhaust through the crossmember, solid engine mounts....

68/70Vette

I think on some years, the engine ground strap when to a nearby point on the frame. You should use a big cable for ground. I could imagine some of the auto store generic ground straps could be a little thin. Also, try to get pure copper. I think some of them have multi-strand aluminum wires. I'd check to see if Lectric Limited sells pure copper cables.

Vetteran'81

How about the 4 gage battery grounds that the part stores sell?

noonie

You can use 2 of them on the same posts.

DRIVESHAFT

On 80-82 cars there should be 2 wires that go directly from the alternator to the battery area. It is odd that your ground wire is the red though. Originally a red one ran from the power terminal on the back of the alternator to a junction block in the battery box. A black wire ran from the back of the alternator to the frame crossmember directly below the battery box. It looks like your car is using the red wire for a ground. Can you tell where the wire that attaches to the power terminal on the back of the alternator goes?

...Roger...

Can't have too many grounds , the more the merrier.

72LS1Vette

Nice to see that they used the standard wiring colors of red (hot) joining to black (gnd). Makes it really easy to troubleshoot problems.



Rick B.

Vetteran'81

Yeah, I could write a book on this car; "The More than Complete Bubba Erratum"

pws69

To establish the best electrical connection, star washers should be between the cable end and the MOUNTING point not the bold head.

Vetteran'81

I removed it completely. Checked and found the stock grounds in place. Everything seems to be ok after a month of occasional driving. I'm sure the PO had a good reason for it, but heck if I can figure out what that was.

Thanks for the advice folks. Love this forum.