trunk mount battery

[racyroy1]

Hey all, I'm building a 340 scamp for racing and I'm mounting the battery in the trunk. Can you run the cables through the passenger compartment or do you need to run them under the car?

thanks guys in advance.

 

[satinblack]

i run mine thru the inside of the car

 

[racyroy1]

good i'm glad i can, cause running it underneath is a big headache, i'm also using 2/0 cable which is kinda big but i got it for free and i want no voltage loss.

ya think i'll be ok :smile:

 

[green1]

Inside ok, but now other problems; Nhra? want the kill switch. alternator, want a 8 gauge wire to the switch, and back to starter relay. While at it ,bypass ammeter. Madelectric. com has it.

 

[racyroy1]

I'll have it so that when the kill switch is hit on the *** of the car the whole car will go dead without a doubt,

 

[SpeedThrills]

What Green1 is saying is, if you're going to run at an NHRA (I guess IHRA, too) track, you have to do it their way.
BTW, ground it at the back, avoid the weight of 2 cables. Run a good ground between the engine/trans and the body if you're not using a motor plate.

 

[RustyRatRod]

green1 is spot on. If I were you, I would grab an NHRA rule book and see. Since you said "race" car, you need to follow whatever sanctioning body regulates the track if you want to be legal. That would be a pretty big violation if they require all that on the outside. I'm sure they'd put you back on the trailer.

 

[waggin]

They even mandate what size and mannor to fasten the battery and box to the frame of the car so check out them rules before ya go at it blindly

 

[crackedback]

This is the safest way to wire it up. Uses a ford solenoid and a S605 continuous duty relay on the alt line.

If you are using the factory wiring/alternator, you need to make an adjustment for the alt field sensing wire.

 

[racyroy1]

What Green1 is saying is, if you're going to run at an NHRA (I guess IHRA, too) track, you have to do it their way.
BTW, ground it at the back, avoid the weight of 2 cables. Run a good ground between the engine/trans and the body if you're not using a motor plate.

I'm in seattle, the track is Pacific raceways and it's nhra. I had read pretty much everything i needed but missed or didn't see the whether i could run the cables inside or out,,, i had a fellow racer tell me inside was fine. I'm not to sure on the one cable run, yea i know it's more weight but I don't mind for the piece of mind knowing that i won't have an issue with a ground but thanks I'm thinking about it now.

green1 is spot on. If I were you, I would grab an NHRA rule book and see. Since you said "race" car, you need to follow whatever sanctioning body regulates the track if you want to be legal. That would be a pretty big violation if they require all that on the outside. I'm sure they'd put you back on the trailer.

well being my first building of a race car I'm sure I'll have my hand slapped a few times. I'm almost guaranteeing that i'm gonna miss something. Thanks

They even mandate what size and mannor to fasten the battery and box to the frame of the car so check out them rules before ya go at it blindly

yea I know, nhra approved box, 3/8 j bolts, they wanna make sure it doesn't flop around for sure.

This is the safest way to wire it up. Uses a ford solenoid and a S605 continuous duty relay on the alt line.

I agree, I'm right with ya on that one. I've a Caterpillar 12 volt solenoid and 60 amp continuous relay also from caterpillar ready and waiting

If you are using the factory wiring/alternator, you need to make an adjustment for the alt field sensing wire.

yessir duly noted. when the battery switch is off the field is opened.



thanks guys ya made me smarter

 

[RustyRatRod]

well being my first building of a race car I'm sure I'll have my hand slapped a few times. I'm almost guaranteeing that i'm gonna miss something. Thanks

Then why not get the rule book follow the instructions to whichever class you're aiming and get it right the first time? That way, you know you won't waste a trip to the track for nuthin.

 

[racyroy1]

Then why not get the rule book follow the instructions to whichever class you're aiming and get it right the first time? That way, you know you won't waste a trip to the track for nuthin.

boy, strokerscamp if you knew me, and i say this in the most humorous way possible, you could staple the most obvious thing to my forehead written backwards for mirror viewing and i'd still miss it. Not the minute details mind you but the most gawdy/obvious thing.

I have a free download of the 2008 rulebook, soon to have the 2010:smile:

 

[RustyRatRod]

boy, strokerscamp if you knew me, and i say this in the most humorous way possible, you could staple the most obvious thing to my forehead written backwards for mirror viewing and i'd still miss it. Not the minute details mind you but the most gawdy/obvious thing.

I have a free download of the 2008 rulebook, soon to have the 2010:smile:

Yeah...it is easy to overlook stuff. Best I can tell you is read, read and then read some more. Do it ONE step and ONE section of the car at the time. You can do it. Everybody else does and they put their pants on one leg at a time just like you do. :thumleft:

 

[SpeedThrills]

I think the best way is to go the the track a few times and talk to racers in the class (or e.t. range) you intend on running, and ask them how they did things. You'll still need to read between the lines a bit, as to what they tell you, but the "interviews" help a lot when it's time to interpret the rule book.

 

[green1]

Forgot: neg to frame ground at rear, don't rely on engine to firewall ground, it will fry(don't ask, lol).Install big cable from block to kframe. If not a one wire, you need a 4 post switch in the rear, to kill the alt (will keep running if not- huge frowns from track staff). And bypass that ammeter, instal a voltmeter.. Get that crap out of the dash. It will bite you before you know it. ( been bit twice, and know people that been bit).

 

[green1]

And don't know whether you have a cell, or not. If so, plastic approved plastic box,vented, $ 80, dammit, steel or alum firewall in backseat area (chassis engingeering). It's a pain. and metal over rear package tray speaker holes...and roll cage tubes sealed, painful.

 

[racyroy1]

I think the best way is to go the the track a few times and talk to racers in the class (or e.t. range) you intend on running, and ask them how they did things. You'll still need to read between the lines a bit, as to what they tell you, but the "interviews" help a lot when it's time to interpret the rule book.

check,,,, I've been racing for a couple of years now. I'm just now building a dedicated car for the track

Forgot: neg to frame ground at rear, don't rely on engine to firewall ground, it will fry(don't ask, lol).Install big cable from block to kframe. If not a one wire, you need a 4 post switch in the rear, to kill the alt (will keep running if not- huge frowns from track staff). And bypass that ammeter, instal a voltmeter.. Get that crap out of the dash. It will bite you before you know it. ( been bit twice, and know people that been bit).

check, I have a 60 constant duty relay for alt fields and a 600 amp disconnect switch for the battery. I have to keep the car licensed and streetable for our club rules .

And don't know whether you have a cell, or not. If so, plastic approved plastic box,vented, $ 80, dammit, steel or alum firewall in backseat area (chassis engingeering). It's a pain. and metal over rear package tray speaker holes...and roll cage tubes sealed, painful.

sporting a 5 gallon cell and am still deciding on the battery box setup.
and yep on the aluminum over the back and speakers....

 

[abodyjoe]

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. At present, Moroso is the only company which offers an NHRA accepted plastic battery box, part number 74050.

But I drive on the street. I don't want a big cut off switch hanging on the back.
This solution takes a little work, but it solves the problem. Install the master cutoff inside the vehicle, positioned "sideways" so that the toggle moves forward and back. Drill a hole in the toggle handle, and attach a steel rod that will run out the back of the car, through a hole drilled completely through one tail light assembly. Have a spare tail light assembly on hand, so when you come home from the drags, you remove the rod and put the cherry tail light back in for street cruising. Next time you plan on going to the drag strip, swap lights and reinstall the rod. Since the drilled light is for the strip only, you can also have it marked "PUSH OFF" in big letters so the Tech Inspectors will think you're cool.

 

[green1]

I drilled a small hole between the top of the bumper, and the rear (don't know the name, but back area with tail lights. put in a handle from a gun cleaning rod to switch. Unscrew it for non track, never see that hole.