My version of the trunk mounted battery

[fordracerguy]

Hey guys. I have just completed my trunk mounted battery. I've done a lot of research and came up with my own version. I would like to note that my installation is NHRA compliant. The only thing left of my installation is drilling a hole in the tail light to pass a rod through to the switch on the other side. I did not do this yet because A) I don't drag race yet, and B) I am not going to drill my 99-01 style tail lights. My idea is to get the tail lights and cut the wires to the bulbs and install a quick-release connector, that way I don't have to swap bulbs too -- that way the lights should stay sealed and there is a less chance of condensation buildup. Anyways, here we go!

The bracket I made for the switch. Uses an existing tail light bolt and a new hole that I had to drill:

What the switch looks like in the bracket:

Wires hooked up:

Test fit - yes!! It fits perfectly behind the trunk plastic:

The battery in the box:

Completed:

Engine bay:

Look at that dirty engine!

Sorry guys, don't have any photos of how I ran the wire up to the front of the car -- thats because you can't see it! I ran the wire over the passenger rear tire (not through the rear seat area.) Pulled it through and ran it along the passenger scuff plate, up through the passenger kick panel, across to the driver side (inside the car) and out the firewall gromet. Keep in mind that to be NHRA legal you must run a second wire (in my case a 4 gauge wire) and it goes from the alternator to the battery (skipping the switch). This way when you shut off the switch, the alternator will not power the car and keep it running. The wire I used for the main power was 1/0 gauge.

Chris

 

[mavereq]

i am just researching battery relocation installs and have few questions:

why did you put it on the passenger side just to run it back over to the driver's sid again?

where did you ground?

what did you do with the stock battery cables?

doesn't the positive wire go to the starter? if so, why run it through the firewall?

 

[fordracerguy]

why did you put it on the passenger side just to run it back over to the driver's sid again?

Well, I figured that when driving the car solo, the car has 200lbs more on the driver side and I was hoping to offset that a bit. I also found a 4 wheel scale weight chart on this board (can't find it now, sorry) that showed that the rear passenger side was the lightest part of the car.

where did you ground?

In the 4th picture down you can see where the blue wire is coming out from top of the plastic in my trunk. Over to the right about 4 inches is where I grounded. There were two metal panels that went together and were punched or tacked to stay together. I drilled this punch out, ground the paint off with a dremel and grounded there. Granted it's not the frame, but I had a short ground wire and gave it a shot. The car is only losing .01 volts at the front of the car from the back, so i'd say is it's doing alright.

what did you do with the stock battery cables?

The fuse box has a plastic cover on the side that can be removed if you pull on it hard. There is a bolt with a nut that holds the positive cables. I ran my blue wire (1/0 gauge) to this spot, and also the starter positive wire goes to this bolt (just like factory wiring). I pulled the alternator charging wire out of the loom because it was no longer needed - since the wire now goes to the back of the car.

doesn't the positive wire go to the starter? if so, why run it through the firewall?

I take it you are talking about running the wire on the bottom of the car? In my experience, I have seen a few trunk mounted batteries with wires ran under the car. I have seen many places that rocks or various things have hit the wire and stripped the plastic down to the metal. Never run a wire under your car, especially because it puts it that much closer to your gas lines.

 

[SVT_4_me]

nice work man... looks like that was quite a project. :thumbsup:

 

[FaYgOkRiS]

I like it, very clean and factory look to the install. My battery switch is welded to my X bar.

 

[fordracerguy]

.

 

[NY04snake]

No intention to muck up your thread but does your "kill" switch actually kill your car when it is running? If it does not it is not NHRA compliant, don't worry, most guys are not. I have a separate, additional 4Ga welding cable running back from the alternator, directly into the battery (that is not like the stock wiring, that shares studs with the starter). That way when my kill switch is activated, the alt dumps into the battery as it spins down but the rest of the car is isolated on the cold side of the switch and goes dead, immediately. I don't see a beather tube with a drilled outlet hole, that is also required by NHRA, as long as your are mentioning "rules".

it should work like this (right click, save as...) http://04snake.com/movies/2006-0304_kill_switch036.mpg

click on the two thumbnails below for a zoom:

 

[FaYgOkRiS]

Hey who figured out how to get to the kill switch from outside the vehicle? AT the drags, they only let me slide cuz they were being nice.

 

[fordracerguy]

Yes, it does kill my car. If you notice there are two red wires going to the battery in the later pictures. The smaller one, a 4 gauge, comes directly off of the alternator to the battery terminal. Kills it quicker than salt on a snail!

You are right on the breather tube. I do have it hooked up to the box, but it is not ran to the outside. I didn't know the ruling on a sealed battery. Is it still necessary to breath the box with one?

Furthermore, I think legalities say that the battery tie down rods must go through the frame of the car. Mine don't. They do go on either side of the frame rail through the trunk floor. Granted on my old car, I had it installed this way. All they checked was to see if the battery and box were solid.

Nice setup by the way! I ran my wires directly to the alternator / fuse box though, to cut back on some resistance loss from connecting two wires together. Granted I need to run a fuse because of the removal of the fuseable link. Do you have a fuse on your setup? Is that what that black thing is on the outside of the box?

 

[CobraBob]

FordRacerGuy, I give you credit for not only the neat installation, but how well you thought this out. Great job! :beer:

 

[fordracerguy]

Thank you very much CobraBob!

 

[CobraBob]

Hey, wanna race our avatars? LOL!

 

[F8LSNAKE]

I'm not sure if you need the vent if the battery isn't in the driver compartment. It being in the trunk of a coupe. Just a thought, but like I said I'm not sure on that.