Battery relocation to trunk + NHRA rules

[Black BNR32]

Hey guys, I'm looking for ideas on where to mount an exterior kill switch and vent tube for a trunk-mounted battery (in accordance with NHRA rules). Currently, I'm running a Taylor box mounted on the passenger side of the trunk.

I think a switch behind the license plate would be neat, as I could remove the plate when at the track. I was thinking of venting through the trunk floor.

Anybody gone through this exercise with an R32?

[Marke]

Remove the rear windshield wiper and put the kill switch there.

[frankiman]

if you use a gel type battery, like Braille's, you won't need a vent tube since no hydrogene is produced by the battery

[Black BNR32]

Remove the rear windshield wiper and put the kill switch there.

hmm, not a bad idea. i'll take a look at that. hopefully the techs at the track are ok with that, as its not quite at the 'back' of the car.

[BeeGTR]

Ive mounted mine on the side in the trunk. I was told that since the Optima is a dry cell it can be mounted on it's side and doesn't need a vent or a box. I havn't had it inspected at the track yet tho.... Can anyone confirm that this will be ok?

[Tony-R32]

I was at the track 2 weeks ago, and the guy didn't even look at what kind of battery was in my relocation box, just told me i needed a kill switch at the back, nothing about a vent though.

[Black BNR32]

BeeGTR, I suspect you will fine without a box as there is a firewall separating the passenger compartment from the trunk. But, i'm pretty sure they will still want to see a vent. You will for sure need a master disconnect switch mounted near the rear of the car, according to NHRA rules.

[BeeGTR]

BeeGTR, I suspect you will fine without a box as there is a firewall separating the passenger compartment from the trunk. But, i'm pretty sure they will still want to see a vent. You will for sure need a master disconnect switch mounted near the rear of the car, according to NHRA rules.

Thanks! I was reading the other forums about relocating the battery to the trunk and I noticed that you cannot run your power wire into the cabin that's where I ran mine.... I'll have to move it under the car

Also a bit ago I was reading an article on weight transfer and they relocated a battery to the trunk on an AE86 and they said moving the battery to the trunk was the equivalent of moving the engine 6" back (closer to the center of the car). It makes sence, 30lbs off the front and 30lbs more in the back means 60lbs closer to a 50/50 weight distribution. When I re-build my car to make it track legal I'm going to move as many fluilds and components as I can to the trunk.

Also any opinions on grounding the battery to the firewall only or running a ground cable to the back as well? I have read many articles saying that if you direct ground the battery to all the major components it's suppose to increase your response. It's suppose to be due to all the interfearance of every electrical component trying to get to the battery. I'm just not sure if it's worth the extra weight...

[Bravo]

You can not put the switch in the window! If the window ever broke the switch will come loose and fall away! Also if the car ever ended up shiny side down it would be inaccessible as well! The best location is in the rear licence plate area, for you very rarely see a car sitting up on it's ass at an accident!
As for the gel batt, no vent needed and no box either! All that it needs is a welded in plate that has solid bolting points for the hold down straps!

[BeeGTR]

Here what I did to mount it. Used a 1/8th piece of Aluminum and put an extra nut ontop so when I pull the battery thru the plate wont fall out.

[Black BNR32]

I have confirmed with my local NHRA tech that mounting the switch where the rear wiper is, is NOT acceptable. I will be mounting mine behind the licence plate.

I am grounding the batter locally, and I have 2 grounds off the engine.

I haven't read any rules regarding the routing of the power wire.

Still not sure how I'm taking care of the alternator.

[Bravo]

You will need stop's on the right to left as well to stop side to side movement as well!

Here what I did to mount it. Used a 1/8th piece of Aluminum and put an extra nut ontop so when I pull the battery thru the plate wont fall out.

[BeeGTR]

You will need stop's on the right to left as well to stop side to side movement as well!

Good point... It's pretty solid, but I dont want that baby going anywhere incase of an accident . . . (knock on wood)

[BeeGTR]

I have confirmed with my local NHRA tech that mounting the switch where the rear wiper is, is NOT acceptable. I will be mounting mine behind the licence plate.

I am grounding the batter locally, and I have 2 grounds off the engine.

I haven't read any rules regarding the routing of the power wire.

Still not sure how I'm taking care of the alternator.

I can't rememeber what has to be done with the alterantor, something like it has to be tied into the kill switch to right? I guess worse come to worse you could run the wire from the alternator to the switch in the back and then it would be able to power up the system from there. Just increase the gauge of the wire a bit. When I re-do mine Im going to go down to 2 gauge for my battery and maybe 4 gauge for the alternator.

I cant think of any other way of doing it.

[frankiman]

this is how it did mine, F*ing solid