Think the 2ga 95amp stuff I picked up at Lowes will work for battery relocation? Auto parts guy suggested Lowes for bulk cable. The sheathing says (UL)600 volts AWG 2 CU type MTW or THWN-2 or THHN or gasoline and oil resistant) Picked up 24ft for about $17. What ya'll think?

Any opinions? Anyone?

Sounds fine. Another good source is a welding shop where you can get bulk welding cable cut to length.

If you are running it outside the car, you can use a piece of plastic electrical conduit for extra shielding. It will run up the centre where the heater hoses are nicely. You can go through the cabin if you want as well.

Make a few good grounds with the neg while you're at it. It doesn't need to be 2 guage.

Thanks, took out A/C and was planning on running both + & - through that channel using some pipe insulation. Any thoughts on terminal blocks for the engine bay?

I wouln't use it.... 95 amps is nothing.... look at the CCA rating of the battery. The starter wiring needs to handle a hell of allot of power.

Keep in mind that the longer a cable is, the heavier it needs to be just to pass the same current as the OE cable. The factory cable is specified as 19 sq mm. (a little under 4 AWG.) You need something heavier than that. Allot heavier since you are going allot farther. I wouldn't go under 0awg.

The new wire also has to be in conduit. Plastic conduit is best, PVC water pipe would do in a pinch.

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11-Sept-01, The day the world as we knew it ended.

I used 2 gauge welding cable for my front mounted battery. It says +105C -50C 600v on it, but don't have amps listed. I think the total length of my positive cable turned out to be about 8 feet, so according to my calculations, 2 gauge welding wire should be more than adequate. I did run a separate 8 gauge cable for my stereo amp. I also ran multiple grounds, one 2 gauge to the engine block and one short ground to the frame from the engine and one short ground from the battery to the frame.

I've seen 6 foot long factory 4 gauge positive cables under the hood of some pickups. What is that wire from Lowe's made for? Is it copper braided wire? At the Ranch supply store I bought my cable at, they had terminal ends that you clamp onto the ends of the wire. You need to get the correct size gauge and the right bolt hole size. For the battery side, I bought streetwire connectors and battery posts from Crutchfields.

Here is the link to my post describing what I did.
https://www.fiero.nl/forum/Forum2/HTML/024195.html

[This message has been edited by batboy (edited 07-08-2002).]

(UL)600 volts AWG 2 CU type MTW or THWN-2 or THHN or gasoline and oil resistant)was all that was on the sheathing, doesn't list actual amperage, the little sign above the roll said 2gauge 95amp. It's braided copper, haven't counted strands but would guess 16 or so. Did not have a specific application listed. It appears to be the same as the 2gauge wire currently in the car. No ends, was going to pick those up at the auto parts store, standard 2gauge ends. The sheathing is stiffer than the auto stuff but says it's gas and oil resistant. The next step up they had was 0gauge 105amp, again this was not on the sheathing but on the sign above the roll. Looking in catalogs I don't see any battery cable listed by amperage only 0 thru 6 gauge. What makes one 2 gauge copper wire handle more amps than another?

The longer the wire, the bigger it needs to be (smaller gauge number). My welding cable is copper braided too, but it has hundreds of individual strands. The welding wire cable is supposed to be the best to use.

According to the chart I have, 2 gauge welding wire up to 10-13 ft. in length should handle 125-150 amps of current. I doubt many Fiero alternators are rated above 75 amps. My guess is you'll be ok with what you have if you keep the cables as short as possible and use good terminals.

[This message has been edited by batboy (edited 07-08-2002).]

Thanks for the input, I may actally be able to shorten the run by going through the interior. The cars pretty much stripped in and out right now and I've been thinking custom console for easier access to shifter, etc. Seems like one project leads to six others. I'm still in need of a bottom end for the 2.8 in this particular car. Dropping the rear this week to start on the backend rebuild. Front end went together really nice, total poly, susp tech springs, monroe sensatrak, upper and lower ball joints and monroe steering stabilizer. The backend doesn't look so inviting.

The reason the temp is printed on the cable is because that's the max, temp the mfgr recommends for the insulation. You could get 95 amps through 10 ga wire easily but it would get real hot real fast. But that's not the real issue. The real issue is VOLTAGE DROP. From the ground return to the battery you want 0 voltage drop, or as close as you can get. I just looked up 2 ga copper wire. The resistance is .0009ohms/ft. Assuming 10 feet of wire and 150 amps (typical starter)

V = IR or V = (.0009 x 10) x 150 = 1.35 volts. So a 2 ga wire would have 1.35 volts drop at starter current. This means that as soon as you hit the starter the block jumps from basically 0 volts to + 1.35 volts potential. This will reduce the voltage through the starter, making it draw more amps. This in turn causes starter winding overheating and early failure.

To maximize starter life you should use no less than 00 ga welding cable and 000 if you can find it. The voltage drop will be about .25v and the car will start easier. You can also provide a good ground at the battery in the front and then run the cable to the engine. Be sure to ground the engine block to the chassis. This will then share some of the amps with the frame. But keep in mind that you will have about .11ohms resistance at each connection and that steel is a lousy conductor. The wire will still carry the bulk of the current.

BTW--Ben Franklin had it all wrong. Electricity actualy flows from the negative terminal to the positive. When you remember that you can remember how important the ground really is.

So how about I run a 0 gauge positive and use the 2 gauge to run the ground back to the block and a ground to the front frame rail? At this point a 10 foot 0 gauge wire would not be that much additional cost, and I want to be safe. Is a terminal block in the front and in the back with dual hot 2ga an option? One 0ga to the block in front and from the block in back? This car is a longterm project so I guess there's no hurry.
Thanks again guys!

quote Originally posted by theogre: I wouln't use it.... 95 amps is nothing.... look at the CCA rating of the battery. The starter wiring needs to handle a hell of allot of power.

That 95 amp rating might be for the 600 volt rating that is printed on the wire. For 12 volts the amp rating would be roughly 1140 amps. Sounds about right for 2ga wire. I used 4ga wire in a battery relocation on a longer car without any issues. The 2ga wire should be fine.

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1987 Pontiac Fiero Coupe #18,838
3800 Series II SFI
4T60-E Trans
3.33 Final Drive

1987 Pontiac GTA
5.7L SuperRam MPFI
4L60-E Trans
3.73 SRD

http://dtcc.cz28.com

You can go to any hot rod or high preformance shop and ask for a battery relocation kit that they use in those pro stock cars it comes complete and buy the wire with ends and all

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85 Fiero (Savage)
345-HP/5SP 4.9 Cadillac.
88 Cradle
11.2" Zettner Brakes
Custom Coilovers
Flowmaster 80's
Keith Dorton 500cfm Carb#0-8583
Edelbrock-70001 3stage NOS kit.
Mallory HY-FireIgnition

What goes around comes around. If you pull 95 amps from the battery it must RETURN to the battery. The ground wire is the most critical. Electricity flows from ground to positive!!!!!!!!!!!!!
You can double up on and use 2- 2ga wires, but each end connection has some resistance, like about 0.05 ohms and is subject to corrosion and heat buildup.

But we are talking about a situiation where you draw large amps continuously, What you want is maximum volts to the starter. Use 0 ga or larger.