Firewall for Trunk w/ Nitrous and battery!

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Jimmy

Jimmy

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Ok so to put it simply trunk has battery on the left nitrous on the right, I know I need to to put a firewall in so whats the best, safe but light material to use? Do I need to put up a partition between the battery and nos or should I put a box around 1 of them? I was thinking a box and kill switch for the battery. Do I need a fuel cell to do this? This is for the strip only and I am a new to it so I humbly ask for your opinions!
Thanks!
 
They have pre-made boxes for batteries, although it's kind of pricey http://www.rpmoutlet.com/musv6batt.htm
And you'd need a pretty stinkin' big switch if your going to put it in line with the main battery cable if that's what you mean. But you could run wires from stuff like the fuel pump, ignition coil, and the nitrous systems power cable (although I'm not sure how the nitrous connects), through one single cutoff switch, that should set you up. And before you do anything, I'd look over the regulations at the local tracks to know what you need. It would be a bummer to set something up and it not pass inspection.
 
IIRC,

Alum is .032"
Steel can be .024"

I don't believe you need to partition the juice bottle from your battery
 
Dry cell might be different too. In hatchbacks most tracks require drycell batteries if they are in the 'trunk' area. I always thought cutting a hole for a nitrous bottle to stick halfway through the trunk firewall would look killer. Oh and make sure you run a blow down tube too.

-Sefus
 
I know you need a partition if you have the fuel cell in the trunk.not sure about it, if you only have the battery and nitrous bottle back there..
 
Aluminum sheet IMO is best. Also, the battery should be on the right for the weight.
 
Not sure but I think fire wall must be metal not alluminum. Battery in box... plastic type like in a boat cheapest. Kill switch must kill every thing. We run Grand Bend here in Ontario and it is NHRA.
 
Thanks for all the input, I think I'm just going to do it all, firewall = Sheet metal, Battery = Sealed & switched, Nitrous = Partition and vent. A few extra pounds won't kill me but trying to shave them in this area just might. It is only street legal's so the inspection and rules are pretty lax until you get into the 11's. As far Battery on the right, it weighs about the same as the nitrous so I think that's only relevant without the bottle.

Here are the rules from my local track for this class.

* Regarding Nitrous Oxide (NO2) - The use of Nitrous Oxide is allowed in all Street Legal classes provided that any Nitrous bottle located in the drivers compartment be equipped with a pressure relief valve and vented to the outside of the vehicle. All Nitrous bottles must be securely mounted (plastic mountingbrackets not allowed), be stamped with and meet the minimum DOT 1800 PSI rating and be clearly identified as Nitrous Oxide

* All batteries must be securely mounted (no bungee cords, rope, wire etc) Batteries may not be relocated into the driver or passenger compartment. Rear firewall mandatory when relocated battery in trunk. If sealed battery box is used, must be vented outside of body. When battery is relocated a master power cut off switch must be installed on rear most part of vehicle.
 
http://www.nhraonline.com/contacts/tech_faq.html

I have a street car that I occasionally run at the strip. I've relocated the battery to the rear. What else do I need?
Any car with a relocated battery must be equipped with a master electrical cutoff, capable of stopping all electrical functions including ignition (must shut the engine off, as well as fuel pumps, etc.). The switch must be located on the rear of the vehicle, with the "off" position clearly marked. If the switch is of a "push / pull" type, then "push" must be the motion that shuts off the switch, and plastic or "keyed" typed switches are prohibited. Also, the battery must be completely sealed from the driver and/or driver compartment. This means a metal bulkhead must separate the trunk from the driver compartment, or the battery must be located in a sealed, metal box constructed of minimum .024 inch steel or .032 inch aluminum, or in an NHRA accepted plastic box. In cars with a conventional trunk, metal can simply be installed behind the rear seat and under the package tray to effectively seal the battery off from the driver. In a hatchback type vehicle the battery box is usually the easiest solution, since the alternative is to fabricate a bulkhead which seals to the hatch when closed.
 
When I first put the battery in the trunk of the Duster, I used 24 guage
steel behind the seat. I was able to use the cardboard panel for a template.
Then just made it bigger to mount it in there. I was still able to put the
cardboard back in ther also. Nice for driving. Alot quieter. The tech guy at
the strip had no problem with it.
It worked out great cause it said 24 guage right in the middle where the
tech guy could read it.
Now with the nitrous bottle in there, no one has complained about the
thickness of the firewall.
What really gets me is the fact that with the rear speakers in there, it's
ok. What would happen to the speakers if there was a fire. Boom!
They never say anything about that.
 
briankaplan said:
What really gets me is the fact that with the rear speakers in there, it's
ok. What would happen to the speakers if there was a fire. Boom!
They never say anything about that.
Click to expand...

Well as long as you have your priorities straight!:headbang:
 
What type of bottle weighs the same as a battery all the time? The reason the battery goes there is it's 15lbs, 25lbs, whatever (I have amonster OptimaYellow top that is close to 40lbs) all the time. You hurt consistancy in your suspension by putting a variable weight there. Just a thought if you're serious.
 
I picked up a light race battery 13.5 lbs (Dry cell Dyna-batt), same as bottle empty but moper you got me thinking about it and I changed my mind, I'm putting the battery back up front on the right (in line with the NO2) I figure it will help balance driver weight better, may not improve 50/50 or traction, but it will save a few lbs and some expense- no firewall, no extra cable, no box, no kill switch = $160 savings plus gotta be at least 10lbs right there.
 
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