I am looking for routing ideas and clamping ideas

Not to be crass...but I've never seen a time when someone posts a question like this that they actually really had such a hardcore drag application that warranted all the work of relocating the battery.

Now that you have endured that run on sentence, here is what happens when you relocate your battery to the trunk:

1) Car will be harder to start. Lengthening the battery cables is electrically inefficient.
2) Generally, you can't do it with just one battery - see #1 above, this is why so many rear mounts consist of TWO batteries.
3) It requires an external battery shut off switch to be drag legal.
4) The only reason to consider this is for drag racing...yet it is rare the car that wouldn't be better off spending the money and time on something like the suspension.
5) If you have an idea that this will so shift the axis of weight distribution read #4 again.

Okay, still determined to do this, get the fattest battery cable possible, preferably something like the special low reistance battery cable wire sold by Taylor-Vertex.

Thomas

I put mine in the trunk because my tray and inner fender were rotten and fell apart.Go to your local welding shop and buy some 2/0 welding wire and run a wire from the starter and one to the block,don't try to ground to the frame(mild steel like a frame will only carry about 170 amps).You can run the majority of the cable through the frame and then use insulated clamps either riveted or screwed to the frame.Then get a hole saw and some mathing grommets and pop a few holes in the trunk and have a beer.

We have done this in both of our BB Chevelles, we race the 65 and the 66 is pretty much a street car with an occassional trip down the track.

1.Both cars start great, you just have to have a good charging system.
2.Both cars run only one battery.
3.Most tracks will require an external switch.
4.Putting the battery in the trunk helps weight transfer in racing but it is not the only reason to consider a battery in your trunk. It really cleans up the engine compartment and there are some added areas to hide an additional kill switch for security.

Summit sells relocation kits with boxes, connectors and cable. As far as routing it is your preference just be sure to clamp good and stay away form moving parts and exhaust. :D

pat just a quick question for you ,are you saying run the ground cable from starter to the block and then ground the block to the fram . just was wondering .my chevelle i have always had problem starting ,a little drag no matter what ive did.now my nova seems to be fine

hey guys,heres a little info i got with my POWERMASTER mini-starter.when attaching battery cable and switch wire,the switch wire should be capable of handling 15A,typically a 14AWG wire.the battery cable must be the proper size for the length of the cable.CABLE RECOMMENDATIONS/DISTANCE (3'=4AWG)(5'=2AWG)(7'=1AWG)(10'=0AWG)(+10'=00AWG.) all connections should be clean and tight and terminals should be soldered if possible.the ground cable to the frame should be the same size as the starter cable.also,a ground strap should be installed from the frame to the motor.if the original solenoid had a connection to the "R" terminal (ballast resistor bypass),this wire can usually be eliminated if running HEI,MSD or other aftermarket ignition systems.here is something interesting:a slow cranking starter can be caused by several things.the most common cause is excessively low input voltage,which can be caused by undersized starter cables,high resistance or defective batteries,high resistance battery disconnect switches or poor connectors.if the input voltage to the starter is satisfactory [9 volts or higher],then a second possible cause could be an underpowered starter.it is important that the starter have the torque characteristics to handle the load of the engine.(duh!)if the engine turns too slow it may require a higher torque starter.

Treestump,

This doesn't directly relate to your question, but I wanted to throw in my $0.02 on battery relocation.

I think that Bowtie hit the nail on the head. Having a properly working rear mount battery isn't rocket science. It's like anything else...do a half a$$ job and expect similar results.

I'm in the process of relocating my battery to the trunk. I'm doing this in hopes of shaving .01-.03 off of my 60' times and with hopes of slightly improving 60' consistency which currently varies by .03. I'll be removing 40lbs off the very front of my car (group 34 battery, doesn't include the weight of battery tray and factory cables) and placing it directly on the rear of my car. This is a common practice for people with nose heavy cars that are looking for max ET. Just look at any stock eliminator, SS or other hard launching A-body car. You will find a relocated battery, trunk/bumper mounted ballast or both. There are a *few* people that have managed to get their cars hooking hard without either of the above, with emphasis on the word *few*.

All that being said I'm using a Taylor aluminum sealed box, Flaming River "Big Switch" disconnect (rated at 250amps continous, 2,500 peak) and 1/0 Scosche high amperage OFHC cable. I'll be running 1/0 cable from the battery to the switch, from the switch to the radiator support terminal and from the terminal to the starter. I plan on running a 1/0 ground strap from the battery to the rear frame and a second 1/0 strap from the engine to the front frame.

Here's a picture of the battery box and FR switch (http://kjett.home.mindspring.com/Images/box2.JPG)

Here's a picture of how I routed the push/pull lever (http://kjett.home.mindspring.com/Images/lever1.jpg) though the rear valance.

Notice the two isolators I installed in the top of the battery box. I added these to make it easy to connect a charger to the battery without removing the lid. I bracket race my car and run the electric fan/pump between rounds. The fan draws 20 amps and the water pump ~10amps. Even the best battery can't hold up to long use of either of these accessories. I have an alternator on my car but it doesn't do any good when the car isn't running and you can't cool the car off with the engine running smile.gif

I realize this modification isn't for everyone. It will change my weight distribution from 57/43 to 56/44. I hope to be racing this weekend assuming my cable and lugs show up so I can finish the job. Otherwise I'll be racing in South Carolina the following weekend. Either way I'll post my results smile.gif

Originally posted by fatrat70:
run a wire from the starter and one to the block,don't try to ground to the frame(mild steel like a frame will only carry about 170 amps).I'm questioning this thought. a frame ground should be good enough. I've seen battery's grounded to the fender with no problems.

Hers's an additional reason for mounting in the trunk. After a hard launch I rasied the hood to find my battery had come loose and fell into the fan. Needless to say I had acid everywhere.

JYD, what I was saying is go directly from the neg. on the battery to the block and off the block to the frame.Your starter is grounded through the block not the frame so to get the most efficient path is through the block.I run 2 2/0 cables one to the starter and one to the block.Your starter will really appreciate it.If you look at a list of the best conductors steel is pretty far down on the list,if you use a 800cca battery and are only getting less than 1/4 of it to the starter then your starter is going to take a beating.

A long time ago I read an article on trunk mounted batterys.It said something about the direction the battery sits.If you mount the battery with the posts facing front & rear,you take the chance of the plates in the battery coming loose on the launch,& touching each other.I guess this wouldn't apply to an Optima style.
Dont know how much truth is involved here,but most stock, car batterys are mounted with the posts facing the right & left fender,not front to rear,,,,who knows. graemlins/clonk.gif

Originally posted by headerfire:
A long time ago I read an article on trunk mounted batterys.It said something about the direction the battery sits.If you mount the battery with the posts facing front & rear,you take the chance of the plates in the battery coming loose on the launch,& touching each other.I guess this wouldn't apply to an Optima style.
Dont know how much truth is involved here,but most stock, car batterys are mounted with the posts facing the right & left fender,not front to rear,,,,who knows. graemlins/clonk.gif Yup, I've read the same thing before. Even considered mounting mine that way. Then I remembered my buddy's SSP-AA Camaro (http://www.ihra.com/gallery/album69/PICT3277) has the battery mounted front to rear and he pulls 1.29 60', carries the front tires beyond the 60' mark, and has never once had a battery problem. Goes to show you can't believe everything you read smile.gif

Does that also mean that the NASCAR vehicles pulling 3 latteral G's would need them mounted front to back rather than side to side? :D

good info here and thanks pat i got you now

heres a juicy tidbit concerning disconnect switches..."the switch used for a battery disconnect is very important.all of the starter current will go across this switch during cranking which,depending on the starter,can be as high as 700A!after the engine is running,all of the current from the alternator will be running across this switch.therefore make sure that the switch that is being used can handle these amounts of current.switches are rated in intermittent amps and continuous amps.the intermittent rating should match or exceed the amount the starter will pull and the continuous rating should match or exceed the amount the alternator can produce.using a switch that is too small will result in voltage loss and possible switch failure." i thought i'd share this in case it might help somebody getting started. :cool:

as high as 700A!after the engine is running,all of the current from the alternator will be running across this switch.therefore make sure that the switch that is being used can handle these amounts of current. That's not true if you wire it using a ford solenoid mounted in the trunk.

The trick is to loop the "batt" and "purple wire" or "s" terminal at the starter, then route the end of the "purple" wire (from the nuetral safety switch) back to the "S" terminal on the new ford solenoid. You then only have power on the + lead to the Starter when cranking (much safer that way).

Wire the cut-off switch from the + lead of the Batt to the fuse block and alternator using 10 gauge which shouldn't see over 30 or so amps.

great advice gatewayracer! graemlins/beers.gif thanks for the heads-up!nuttin'like a good education!

Sorry, didn't mean it to sound like an "education", but I recently did allot of research on the subject before moving my battery to the trunk and wanted to share. It seems good wiring diagrams to do this on early Chevy’s are hard to come by on the net; I'll post a wiring diagram if anybody wants it.

I agree with your statement that you need a good cut off switch (if the starter cable goes through it). Even the Moroso switch is only rated at 250 amps, and for that reason I chose to go the route of installing the solenoid. Also going the solenoid route the switch is only supplying power to the fuse block and return for the alternator, but it still needs to be a minimum of a 75 amp rating.


graemlins/beers.gif

Originally posted by gatewayracer:
It seems good wiring diagrams to do this on early Chevy’s are hard to come by on the netThese are excellent: http://www.madelectrical.com/electrical-tech.shtml

Thanks Ken, That is a good link, Although I did not see a diagram to add a ford type solenoid, cut-off switch and relocate it to the trunk.
BTW, have you made the move to a trunk mounted battery yet?

They sell a battery relocation kit that uses a solenoid just like you described. Here's a link complete with diagram:

http://www.madelectrical.com/catalog/tm-1.shtml

Here's the second part:

http://www.madelectrical.com/electricaltech/chevymain2.shtml

As for me, yes I just completed my battery relocation project. The picture is a little deceiving. The cable is not interfering with the switch lever, just a funky angle of the camera.

http://kjett.home.mindspring.com/Images/battdone.JPG

I'm sorry to say that I didn't use the solenoid method. I ran a 1/0 cable all the way from rear to front. Starter worked fine when I tested it last night. I'm heading to the track today to see what sort of difference this made if any. If I had it to do over again I would strongly consider this kit that MAD is selling. The price is reasonable and the idea of using a solenoid could prevent a unwanted fire should the *live* wire running from the front to the rear ever become hard shorted. I may put a solenoid on mine later.

Very nice job Ken, Those aluminum boxes are not cheap but they look good! With the box 2/0 wire, switch and miscellaneous, I'm guessin you have over $300 invested. As long as you're wire isn't near any sharp metal or moving parts, you shouldn't have to worry about any fires. I don't think the solenoid is a "must have", It's just the way I did it.

I like the idea of the solenoid, but I also get the feeling NHRA tech might not like it. A solenoid can stick in the open posistion (most likely when the starter's engaged). Other than the possibility of a continuous(sp?) cranking problem, the Ford solenoid seems to be a nice alternative.