Relocating a Battery

Moving the battery to the trunk has several advantages

Think of your battery as a 60-pound lead weight—because that's exactly what it is. In most vehicles, it's mounted far forward and just low enough to clear the hood for easy access and maintenance. Performance enthusiasts and hardcore drag racers discovered that relocating this massive weight to the trunk improved the static weight distribution for better traction. OE auto manufacturers such as BMW place the battery under the rear seat to improve weight distribution and cornering capabilities. The mass of a battery doesn't sound like much compared to the overall 4,000 pounds of vehicle mass, but when you think of that 60 pounds out on the end of a 15-foot lever, its location takes on more significance.

We wanted to relocate the battery to the trunk in our late '60s GM A-body for a number of reasons. First, it's a modification in keeping with the musclecar era just like headers and traction bars. Placing the battery as low and as far rearward as possible would greatly improve off-the-line traction and overall handling. More significantly for this daily driver is that we are installing a new Sears DieHard Security battery as an anti-theft device, and keeping it locked in the trunk adds another level of security. Finally, from an aesthetic point of view, engine compartments look much better without that black lump up front in full view. And for those restorers who are purists, this restomod is easy to undo. Just six holes in the trunk floor and a few small holes in the frame to fill.

In our '69 Buick GS 400, moving the battery to the trunk prevented us from mounting the spare tire in its original position. Your vehicle may suffer from a similar problem. We're going to get around this problem by carrying a later model space-saver spare.

Once you commit yourself to the modification, you need to purchase the components for the changeover separately or in kit form. If you're looking for a high-end billet aluminum battery box and hold-down, the street rod market has plenty of options available. We wanted a '60s period-correct trunk battery tray and hold-down and knew right where to get it. Mopar Performance has offered a complete battery relocation kit (part #P4349500) for years, and it has everything you need to complete the swap. It retails for approximately $100, which is a bargain compared to running around and buying the individual pieces.

The Mopar Performance kit contains a large stamped steel battery tray, a long O-gauge copper core positive battery cable, a short negative battery cable, battery terminals and various heavy wire and terminals for wiring the starter solenoid.

The actual restomod project is a perfect Saturday afternoon project. Plan 4-5 hours to do a clean installation. Other than the normal hand tools, you'll need a 9/16-inch diameter hole saw to cut holes for the battery cables to pass through to the trunk floor. A couple of other tips: Use a maintenance-free battery to eliminate acid spillovers in your trunk. Make sure that your battery is in top condition. There's a voltage drop through the long positive battery cable that requires a battery to be in top condition to ensure consistent starting.