Moved the battery to the rear of the car? If you have I would like to hear about how you did it.

This is something I have been wanting to do for quite some time now.

I have an optima battery, moroso relocation kit, a cut-off switch - I just need to get up the gumption to tackle the project.

Wanted to move it to the storage compartment in the rear.

 

Super good question!! I was just getting into move the battery myself so this is very timely. Having a real problem with traction. Good un!!

 

You would want to seal the compartment and then vent it to the outside of the car. I would be worried about fumes from the battery getting into the interior.

 

Its a sealed battery that can be located anywhere in any position.

 

Where did you get the relocation kit and what did it cost if you don't mind me asking?

My assumption is the cut-off switch is for NHRA rules??

 

I don't have one in the vette but had done this in other race cars I have owned. Something you may want to consider is the effect in the location you choose, across the centerline of the rear end should act as nuetral weight and positioning it further back can (if I remember right) should add to the weight transfer. I also think if you are using only one, the placement could be used as an advantage to the way a car twists or 2 to distribute the weight evenly. They used to also have battery covers for exposed in the vehicle app. Just a thought

 

The battery relocation kit is from summitracing.com. But basically the only pieces I will use will be the hold-down rods to secure the battery.

The cutoff switch is required for any movement of the battery from its usual position.

I feel the back right of the car would be a huge improvement in weight tranfer. If you watch my car leave in this video, and figure my added weight is on the opposite side, ABS unit etc is all making the left side of the car heavier. THis was before the tire change, and you can see the right of the car come up higher than the left. This movement of weight might help even out the car.

jttp://www.azzatochips.com/Beaver9-30-05/jesse10_25_1400.mpg

I about died when I saw how much of a difference the ultra-light front wheels 1" higher made the last time out. I was pulling wheelies 1.5-2' high to the bottom of the wheels and dead hooking better than ever on a completely unprepped track.

Moving that battery weight to the back would be HUGE. The tires were only 18lbs less.

 

I did it, not much to it really.
Bolt the batt. box to the floor of the storage compartment,
Drill 2 holes for the cables ... I used the original ground location & of course the starter. Strapped the cables to the C-beam & fire it up.
If you would like to call & jar my memory for details feel free
864 313-6626
Anthony

 

What did you do with all the + side connections that are behind the battery? Did you run two lines, one to the starter and one to the + side connections behind the battery?

I can probably figure it out when I finally commit to doing it, but if you have any pointers it would be great.

Did you just connect the alternator line to this + side behind the battery?

 

Does NHRA still require a sealed battery like this be mounted in an approved box? I understand that you don't need to do this, I am just wondering if NHRA buys that.

 

Here's what I'm going to do when I relocate mine. Get a remote solenoid switch such as the old Fords used for their cranking system. After hooking the battery positive to it, run another cable (from the other side of it) to the starter. Jump this to the small post on the starter. Use the wire that formerly triggered the starter to trigger the remote solenoid. Now you can run your alternator + wire to the battery side of the remote solenoid and run a wire from there to the junction near the original battery location. This removes all current from the starter area except when the starter is engaged and except for the cable and the jumper from the large to the small post, removes all wiring from this hot area as well. Make sure the base of the remote solenoid is well grounded and it will be trouble free.
And if you locate the solenoid where the battery was, you can use the original cable already going to the starter if it's in good shape, just change the end from a battery terminal to a HD ring terminal.

 

Mine's in the passenger side storage compartment Jesse... It's not hard and if you plan on running a kill switch it's much easier in fact with the battery in the rear. A standard Vette battery will fit in the compartment but it's a PITA to get in there. I originally used one of those but will be using a smaller Optima when I put it back together.
-Jeb
-Jeb

 

I have mine in the same place. Passenger side rear compartment. My kill switch is located where the reverse light used to be.

The kit I bought is from summit and the battery is a little sealed oddessy from summit as well.

 

It would be really interesting to see how much % wize your increasing the force at the rear tires. I'm sure its a good amount as you are taking the weight off the nose and putting it on the rear.

Also, the most effective spot (lenght of the car wize) would be the maximum distance from CG with the car positioned like its leaving.. so if your pull wheels by a foot when you leave it would be better to put the battery a little higher and closer to the center of the car.

This would be a neat dynamics problem if someone wants to take some wheel base measure ments and a stab at where the CG is.. oh and a avg accleration

 

I put an optima in my rr storage compartment.

I routed the cables inside the driver's side rocker panel up to the original location and added a quick disconnect there (the large grey connector near the msd in my photos).

Basically preserving the orignal wiring except for the side post connectors, which were cut off and replaced by the connector terminals.

One problem with the cables routed inside the rocker panel: this is also where the vss wires are routed, and I get some noise on my speedo when stopped which can be annoying.

see my corvette photos for some pics

I also added another short ground to the rear bulkhead.

 

Jesse,

 

Jesse, All you need to do is shim up the lower tub to get a level platform for the battery to sit on in the storage compartment. Then run an 0 gauge battery cable from the starter back on the outside of the c-beam with several tie wraps to secure the cable away from the drive shaft. this goes back to your + batt terminal. Drill 2 holes or one large hole for both battery cables to enter from the drive shaft side of the box. The Neg batt cable bolts on the side of the C-beam where convenient. Take the existing positive cable where it sits by the driver's side fender and bolt it through the plastic fender housing to keep it secure from flapping around. The negative cable should bolt directly to the frame where the battery used to be. Get a cross-over bracket for the top of the new battery location and two side rods to bolt through the floor of the storage compartment. I ran a piece of bar stock steel under the outside of the storage compartment box to give it strength when you tighten down the battery side bolts. It has worked well for me with near +1.0gs lateral during my autocrossing. No problems. Good luck ! Dave

 

I moved an Optima to the passenger storage compartment. I do not use a hold down, but the base is very tight in the storage compartment, and the battery has no place to move.

All wiring runs down the R side next to the framerail (interior of the car) and exits the passenger compartment just under the heater box. I ran a 0 ga cable from the battery to the cut-off switch located under the rear cargo area with a single actuation rod exiting the rear bumper area. Then both the + and - cables run to the front of the car. On the cut-off, if it is in, it is energized, if pulled, the circuit is cut. This comes in real handy when working on the car.

I relocated the battery when I pulled the complete engine harness and merried it to the FAST harness. Mine has been this way for over three years with no issues.

Aaron

 

I just ran the math on this.. Something I didn't think about until I started looking at the formulas is that you can actually do some good by not only moving it to the back but as high as you can get away with.. Not entirely obvious.. but think about it. hold a brick verticle and move it fast then take it and hold it horizonal and move it fast.. which rolls harder?


PS.. my 3500lbs Fbody with 101.1 wheel base during the first 60' picks up a even average 50 lbs on the back tire when I move a 35lbs battery from the front to the back of the car. COM changes by about 1.5 inches. (this was modeled on a 1.70 60')

 

I've studied this in detail and offer a few observations. These may improve your safety / performance / nhra-ihra compliance:

1) For optimum performance, you want it as far rearward and to the passenger side as possible. IMHO the pass side storage compartment, being in front of the rear wheels, does not meet this requirement. Also, the way I interpret the rules, there is no way that bolting the battery just through the fiberglass will comply.

2) The switch must shut off a running engine. The engine will continue to run on alternator alone. Therefore the alternator must be shut off. With the High current alternators used in street cars, the only practical way to do this is to cut the alternator field coil circuit. Get a switch with two independent (isolated) sets of terminals (such as moroso heavy duty), use one set of terminals for the battery positive, the other for the alternator field ground. If you take apart the alternator, you can cut the ground wire on the field brush, and run it out to a wire. (not that hard, if your are mechanically inclined ... easier on reman / autozone alternators). Ground that wire through the switch. On the Moroso switch, the small contacts break before the large ones, which is perfect (no alternator damage that could result from battery being disconnected first)

3) NHRA requires that the battery positive be broken. This is a potentially dangerous requirement. Stock car sanctioning bodies require the opposite. The positive is always at risk to short out to the body or frame in an accident, even if the switch is open. Fortunately the vette body is fiberglass, so there are fewer conductive surfaces to contact the switch or wires, making it a bit safer. But, out of my concern for your safety, and not to criticize any other recommendations ... I would not mount the switch in the license or similar area. Why? ... If there is a rear end impact, the positive wires, and switch contacts/studs will be crushed against the aluminum rear frame, causing major sparks and heat, right by the soon to be crushed gas tank ... a very serious fire / explosion risk. This may however be a reasonable location, if you chose to thwart the letter of the NHRA rules (in the name of safety) and break the battery ground cable with the switch instead.