Trunk Mount Battery

[sperold]

I have wanted to mount my battery in the trunk for awhile now, but one thing is stopping me. I don't know where to run the cables. Getting the cables is no problem, but I would prefer to run them externally on the underside of the car... mainly because I have no idea where they could enter the cabin at the firewall. Does anyone have pictures of an install that could give me inspiration?
If the cables were run externally, where is a good place to enter the trunk area?
Has anyone done this?

 

[firebat45]

Everyone with the standard SC kit has relocated to the trunk. Just get a grommet or two (depending on how you wire it) and put them where convenient for the battery mounting.

Not sure what you mean by enter the cabin at the firewall, they don't need to do that. Go straight from the battery to the starter, that's it.

 

[sperold]

Am I missing something?
I had thought that I would have to run both the positive and the negative cables from where they are now, back to the rear mounted battery. And stuffing those big cables throught the firewall takes a lot of guessing as to where they can go through. That is why I thought running both cables under the car was less risky.

 

[pitaSHO]

I put mine in the trunk and ran the cables inside the car. They went under the edge of the carpet all the way to the firewall. Remove the trim up there and peel back the carpet. Pre-drill a hole where it looks like it won't hit anything. Then use a step drill bit until the hole is just big enough for the rubber grommet. Use monkey snot to get the cable through the gromet. It should be a tight fit. Then I used some small plastic hangers to hold them up in the fender well and ran them into the engine bay behind the washer fluid tank (I think) then down the front of the motor and hooked them up to the starter as usual. I would suggest shielded cable, though. The speaker wires are right there and pick up interference from the current through the battery cables.

Hope this helps.

Chris K.

 

[firebat45]

Am I missing something?
I had thought that I would have to run both the positive and the negative cables from where they are now, back to the rear mounted battery. And stuffing those big cables throught the firewall takes a lot of guessing as to where they can go through. That is why I thought running both cables under the car was less risky.

I don't personally like running them through the cabin, if there was ever a problem where they shorted out it could be dangerous (more so than under the car, at least). I'd use grommets to get under the car right away, in the trunk, then run the cables up along the same route as the fuel lines, but the opposite side of the car.

Also, most people don't run a negative up to the front. I think that's a mistake. All the starting current is then forced to go through the chassis of the car and the small ground straps at the motor. Some people just put a thick ground strap from the engine bay chassis to the starter, but I prefer to run both cables up to the front.

If you want to do a really nice job of it, find somewhere to mount some boost points, and a disconnect switch.

 

[Lupo]

Don't forget to run the ECU ground directly to the battery in trunk. If not, you might have some problems with the ECU that you'll never be able to figure out.

 

[sperold]

I had trouble running a comparitively tiny wire for my amp in the trunk, so those monster cables look out of the question for me, but I do appreciate the interior routing information, pitasho, in case I get ambitious. I am going to proceed with the routing advice from firebat as that will be easier for me with my skill set.
I have always thought that the battery should be in the trunk, since there is so little room in the front to begin with. And the weight.

 

[kevinspann]

Don't forget to run the ECU ground directly to the battery in trunk. If not, you might have some problems with the ECU that you'll never be able to figure out.

Where/what is the ground for the ECU? Is it that second smaller wire that comes off of the negative battery terminal?