NHRA Legal Battery Box Mounting

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exST165

New member
Does anyone here have experience mounting a battery box? NHRA rules say that the two 3/8" bolts have to go through a frame rail.

I wanted to mount the box in the rear seat area on the passenger side (with LHD, so right side of the car) but there doesn't appear to be enough space on the frame rail between the bracket for the exhaust hanger and the subframe. The only place I can see is in the trunk on the frame rail that runs above the exhaust, but its going to be a tight fit.

What have people here done?

TIA,
Thomas
 
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fhalperformance

New member
I have mine mounted in the trunk over the exhaust. Its not the easiest install but its functional. I actually made a mistake and had to redrill the box to move it because I still have the plastic pieces installed and I wasnt thinking clearly when I drilled the holes. I can get you pictures later if you want/need them.
 
E

exST165

New member
Thanks but I have found a spot that I think will meet the letter of the regulation and with some welding will be safe.

I'm putting it where the rear seat used to be on the passenger side, one bolt is through the longitudinal frame rail and the other is going through the lateral structure where the floor pan kicks up to the back seat. The lateral structure is boxed in so I say it is a frame rail, but because of height differences I need to weld in some supports.

Thomas
 
CMS-GT4

CMS-GT4

Active member
fhalperformance":3oxhvf6a said:
I have mine mounted in the trunk over the exhaust. Its not the easiest install but its functional. I actually made a mistake and had to redrill the box to move it because I still have the plastic pieces installed and I wasnt thinking clearly when I drilled the holes. I can get you pictures later if you want/need them.
Click to expand...

I would like to see pics.
 
S

SBCelicaGT

New member
CelicaBatteryGround1.jpg


(Disregard the stupid location of the grounding cable. Rather than welding a tab to the chassis, I ultimately decided to run a large cable back to the engine)

This passes NASA's safety inspection. I don't believe a sealed box is needed as this is a spill-proof type battery.
 
8

88st165

New member
90TURBO4WD":1g84z5fs said:
Do you need an exterior kill switch with a trunk mounted battery?
(kill switch on rear bumper etc.)
Click to expand...

does anyone have pics of how they mounted or wired theirs.... i was thinking of putting a switch where the trunk lock cyl is located so i can be easily switched back with no added holes in my car...
 
E

exST165

New member
90TURBO4WD":33v2tfhz said:
Do you need an exterior kill switch with a trunk mounted battery?
(kill switch on rear bumper etc.)
Click to expand...

Everything that I've read says that NHRA rules demand a cut-off switch if you relocate the battery, but I have yet to talk to a tech inspector in person.

This guy quotes the rules. Note that by the letter of the rules it has to do more than just cut the battery, it also has to disable the alternator to ensure that it stops the motor if the switch is activated.

http://www.varacers.com/index2.php?opti ... df=1&id=43


88st165":33v2tfhz said:
does anyone have pics of how they mounted or wired theirs.... i was thinking of putting a switch where the trunk lock cyl is located so i can be easily switched back with no added holes in my car...
Click to expand...

One way is to use a push rod to activate the switch so you can remove the push rod when you aren't at the track:

http://www.gmhightechperformance.com/te ... index.html

http://www.mustang50magazine.com/projec ... index.html


Or mount the switch behind a tail light that you remove at the track:

http://www.dsmtalk.com/forums/showthread.php?t=181965

I have seen other sites, but I can't find them right now. Google is your friend, good luck.

Thomas
 
T

turbo4wd

Moderator
exST165":3rirulvq said:
Everything that I've read says that NHRA rules demand a cut-off switch if you relocate the battery, but I have yet to talk to a tech inspector in person.
Click to expand...

Shortly after I had relocated my battery I went back to Fontana for the street drags they have there and tech inspection wouldn't pass my car because it wasn't equipped with a kill switch.

I had plans on mounting a switch behind the license plate but never got around to it.
 
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