Battery in truck...cable under car or inside?

Posted By: tywebb2

Battery in truck...cable under car or inside? - 10/11/11 02:08 AM

I am going to upgrade my battery cables from 2awg to 2/0. The old cable ran from my battery in the trunk under the car up to the starter. It snaked around suspension parts through and over frame connectors and was tight in places so running the 2/0 in the same path doesn't seem possible. I would rather run the cable through the trunk along the left sill under the carpet and through the firewall to the starter. Is it ok to run the cable through the interior?

Posted By: gsmopar

Re: Battery in truck...cable under car or inside? - 10/11/11 02:29 AM

Mine is in the interior. I don't know if it's legal, but that's where it is!

Posted By: MR_P_BODY

Re: Battery in truck...cable under car or inside? - 10/11/11 02:41 AM

I will assume you are asking if its legal... yes it is

Posted By: tywebb2

Re: Battery in truck...cable under car or inside? - 10/11/11 02:45 AM

One more thing.....now I have the engine grounded to the frame in the front and the battery grounded to the frame in the rear. Is that ok or do I need to run a negative from the battery up to the engine?

Posted By: MR_P_BODY

Re: Battery in truck...cable under car or inside? - 10/11/11 02:51 AM

I weld a stud to the frame... front and rear and use
that as the ground.... then run a ground to the engine
besides using the motor plate

Posted By: topside

Re: Battery in truck...cable under car or inside? - 10/11/11 03:30 AM

Mine run through the interior, following the factory harness route along the left side. Perfectly legal. Just make sure to use grommets or a short length of rubber hose at possible chafe points.
Short ground at the back and one at the front are fine, no need for a full-length neg cable.

Posted By: tywebb2

Re: Battery in truck...cable under car or inside? - 10/11/11 04:03 AM

Great thanks. I hope to have the new cables this week to install over the weekend. Hopefully they eliminate the hot start issues.

Posted By: rowin4

Re: Battery in truck...cable under car or inside? - 10/11/11 04:13 AM

If you have a uni -body, use your old #2 wire as the new ground from rear to front on the engine, you will notice the difference in starting

Posted By: Cab_Burge

Re: Battery in truck...cable under car or inside? - 10/11/11 04:16 AM

Quote:

Great thanks. I hope to have the new cables this week to install over the weekend. Hopefully they eliminate the hot start issues.

You can never have to many ground straps, just like money, fun, common sense, HP, traction and so on

Really, all kidding aside, make sure and ground the holy beholy out of it

Posted By: Dads426

Re: Battery in truck...cable under car or inside? - 10/11/11 12:12 PM

Quote:

If you have a uni -body, use your old #2 wire as the new ground from rear to front on the engine, you will notice the difference in starting

Steel is a poor conductor of electricity. That, coupled with all the rusty spot welds on a unibody will benefit from a separate ground.

Posted By: ahy

Re: Battery in truck...cable under car or inside? - 10/11/11 10:35 PM

Quote:

One more thing.....now I have the engine grounded to the frame in the front and the battery grounded to the frame in the rear. Is that ok or do I need to run a negative from the battery up to the engine?

On where to run... safe to say there is non consensus. I ran mine outside the pass compartment. In case of problem, accident ect. the cable is a source of sparks and heat so I wanted it outside. I ran mine (1 guage) using a routing similar to the factory fuel line except on the left side. Lots of clamps and ribbed wire cover to prevent chafing.

On many cars, the chassis ground alone is enough. Just make sure your ground lugs catch more than sheet metal in the trunk or the fender apron. I caught a rail re-enforcing plate in the trunk and the edge of the front framerail in the front for my ground lugs. A seperate ground wire back to front (#2) added later still helped hot start.

Posted By: tywebb2

Re: Battery in truck...cable under car or inside? - 10/12/11 12:45 AM

Good idea using the old #2 cable as a separate front to back ground. Why didnt i think of that? Right now I have a ground from a starter bolt to the frame in the front. I have a second ground from the battery in the back down through the trunk floor and boltedthe the frame rail below. Could I just run the front to back ground from a motor mount up the right side and bolted the the frame using the same bolt that the battery ground strap attaches at? Or would it need to run up to the negative battery post doing away with the short battery ground?

Posted By: coronetville

Re: Battery in truck...cable under car or inside? - 10/12/11 01:02 AM

look at the battery cable system that spaghetti menders sell

Posted By: Bob_Coomer

Re: Battery in truck...cable under car or inside? - 10/12/11 01:45 AM

I will say that the negative side of your typical race car is usually sub par, when really it needs to be just as good or better than the positive. Considering the negative side of the battery is what really is Hot, and provides the flow of electrons.
In reality the whole frame is energized waiting to jump on the starter, fuel pump, fan what ever when the circuit is closed

They figured this out in the 40's and 50's but didnt want to change the standard system and battery around, causing more trouble and confusion.. but when it boils down it works the same way, but this is why the ground side needs as much attention as the hot side.

Posted By: 70HemiGTX

Re: Battery in truck...cable under car or inside? - 10/12/11 04:41 PM

I have two ground wires from my engine block to the frame rail. One on each side. Then I have a 2ga. ground wire from the battery to the rear frame rail. If it isn't grounded well enough you will find out. Just try to start the car at night w/o any lights on. Any where you have a really close metal/metal point you could see sparks. Don't ask me how I know. My brother pointed this out to me one evening when he was visiting. I was getting an arc between my one header pipe and the inner fender.

Not good. Put another heavier ground on the block and took care of that. Starter spins much faster now also.

Also go to NAPA and get a heavy duty fuse to put in your positive wire. I have a 300A fuse in mine. Yes it will still do some welding if the wire gets cut, but not as long as it would if it were not fused.

Posted By: tywebb2

Re: Battery in truck...cable under car or inside? - 10/13/11 01:19 AM

Is the 300amp fuse something I need to get professionally installed in the line or does it bolt on one end? Any one have a link to one online?

Posted By: AtomicDog

Re: Battery in truck...cable under car or inside? - 10/13/11 03:33 AM

Here are some alternate points of view as to how you might perform your trunk mounted battery wiring - see the diagram at the bottom:

http://www.madelectrical.com/catalog/tm-1.shtml

Posted By: Cab_Burge

Re: Battery in truck...cable under car or inside? - 10/13/11 04:06 AM

BTW, I run my cables inside the car under the sill plates to the fireweall and then out to the starter or starter relay

Posted By: 70HemiGTX

Re: Battery in truck...cable under car or inside? - 10/13/11 08:15 PM

Quote:

Is the 300amp fuse something I need to get professionally installed in the line or does it bolt on one end? Any one have a link to one online?

Go to NAPA.com and type in 300 amp fuse. The fuse and fuse holder should come up. Nice holder that you can screw fast some where and then just bolt the cable ends to the mount. Simple!

Posted By: tywebb2

Re: Battery in truck...cable under car or inside? - 10/14/11 02:50 AM

So I would take the line from my battery positive and bolt the lug end to the 300 amp fuse and then bolt the fuse to the post on the kill switch? Its that simple? The pic I saw on napa website looks like a fuse in middle with lugs to bolt to on each end. Is that the right one?

Posted By: 70HemiGTX

Re: Battery in truck...cable under car or inside? - 10/14/11 03:05 PM

Actually use their fuse holder. That way there isn't any stress on the fuse itself from the battery cable or vibration. Just cut your battery cable and put two ends on it and bolt them fast.

Posted By: MR_P_BODY

Re: Battery in truck...cable under car or inside? - 10/14/11 03:33 PM

Quote:

Actually use their fuse holder. That way there isn't any stress on the fuse itself from the battery cable or vibration. Just cut your battery cable and put two ends on it and bolt them fast.

Post a link to the holder if you would please... I
dont see the holder

Posted By: sshemi

Re: Battery in truck...cable under car or inside? - 10/14/11 06:04 PM

If you have it in the truck why about the wireing in the car? Sorry but i couldnt resist

Posted By: tywebb2

Re: Battery in truck...cable under car or inside? - 10/15/11 12:22 AM

I am interested in seeing the holder as well. I ordered the fuse today for pickup tomorrow.

Posted By: POS Dakota

Re: Battery in truck...cable under car or inside? - 10/15/11 12:45 AM

If it's a truck that's simple....just run it up over the ladder rack.

Posted By: mopar400

Re: Battery in truck...cable under car or inside? - 10/15/11 02:32 AM

Holder is HERE . Kevin

Posted By: tywebb2

Re: Battery in truck...cable under car or inside? - 10/15/11 03:01 AM

Got it. Thanks.

Posted By: 1964superstock

Re: Battery in truck...cable under car or inside? - 10/15/11 03:41 AM

Quote:

Here are some alternate points of view as to how you might perform your trunk mounted battery wiring - see the diagram at the bottom:

http://www.madelectrical.com/catalog/tm-1.shtml

I have spoken with Mark at MAD Electrical about trunk mounted batteries. He does NOT recommend using a ground cable from the trunk mounted battery to the starter. He has told me specifically to only use the body as the ground. He also recommended using a 2 large ground on cables (1/0) on the engine to body.

Posted By: 70HemiGTX

Re: Battery in truck...cable under car or inside? - 10/15/11 04:13 AM

Quote:

Holder is HERE . Kevin

Yup that's it. Thanks for posting that. I was at work and just got home. Plus if anyone can screw up a link to something........I can.

Posted By: RobX4406

Re: Battery in truck...cable under car or inside? - 10/15/11 05:06 AM

What about using the cage/roll bar, if you have one, as a ground medium. Weld a stud near the battery, another on the A-pillar Bar, snout bar or door bar and connect ground to engine/frame at front.

If you use a ford/remote start solenoid, you don't need to worry about that honking 1/0 or so wire being hot all the time and require a fuse holder. I prefer it be cold any time except in start mode.

There are a bunch of ways to wire the car with a battery in the trunk.

Posted By: 67mprfan

Re: Battery in truck...cable under car or inside? - 10/15/11 06:35 PM

Quote:

If you use a ford/remote start solenoid,

part # for the solenoid as i will be wiring my car in a couple days

Attached picture 6872599-63250012.jpg

Posted By: mopar400

Re: Battery in truck...cable under car or inside? - 10/16/11 12:35 AM

Quote:

Quote:

Holder is HERE . Kevin

Yup that's it. Thanks for posting that. I was at work and just got home. Plus if anyone can screw up a link to something........I can.

No problem

I just got my car running again and I'm getting ready to update my wiring. I had the page up for my parts list.

Posted By: Super Scamp

Re: Battery in truck...cable under car or inside? - 10/16/11 01:15 AM

How many Electrical goooroos do we have in this post

The correct way to install a battery in the trunk is to switch the negitive side in the rear of the car.(Race Car)Potential to ground using #2copper to the Rollcage with stud welded to cage. #2 copper to Master switch in dash then to relay control. Or what ever your running for a switching system. Switching the - cuts everything off then High amp switch in dash + will controll what you want to shut off from inside of car. (Starter,Fuel,Alt,) This is just a start to a wiring madness you can create..

I run my cables in the inside of the car.

Posted By: racerx

Re: Battery in truck...cable under car or inside? - 10/16/11 01:53 AM

Quote:

Quote:

Quote:

Holder is HERE . Kevin

Yup that's it. Thanks for posting that. I was at work and just got home. Plus if anyone can screw up a link to something........I can.

No problem I just got my car running again and I'm getting ready to update my wiring. I had the page up for my parts list.

Nice chally

Posted By: tywebb2

Re: Battery in truck...cable under car or inside? - 10/16/11 04:34 AM

Napa part#'s
300 amp fuse. 7822205
Fuse holder. 7721143

I picked mine up today and it is a nice looking piece. I ended up running my new 2/0 cable under the car again. I also installed a new 2/0 ground from the engine up front to the frame rail and another 2/0 ground from the battery to the frame in the rear. I also reused my old 2ga cable as a ground from the bell housing in the front to the battery negative in the trunk. New contactors and plungers in the mini starter too. Starter turns over without any drag now. Real test will be tomorrow when I take it out and see how it starts when heat soaked.

Looks like I may have it ready for the track next weekend after all.

Posted By: Allan_G

Re: Battery in truck...cable under car or inside? - 10/16/11 05:48 AM

Quote:

How many Electrical goooroos do we have in this post...The correct way to install a battery in the trunk is to switch the negitive side in the rear of the car...

While it's a better idea to put the battery disconnect switch in the negative side, the last time I checked, NHRA, in their infinite wisdom, states that the switch must be in the positive side.

As for the OP's question, I run my cables inside until they get to the front firewall. However, my starter cable wire is not full-time hot because I mounted my starter solenoid in the trunk right next to the disconnect switch. Also, the other hot wires going forward [1) from the alternator and 2) to the main power distribution area] are protected by fusible links, just in case they were to ground out. Those are the short greenish-blue wires in the pic.

Attached picture 6873471-DSC00059.JPG