Battery Relocation Page


To install a big downpipe, you may want to consider moving the battery to the trunk or under the back seat. That gives you extra room for the downpipe and eliminates the chance of ruining the battery with the heat of the exhaust.

Moving the battery is a pretty easy thing to do, however it is a bit of work as you need to rip apart the interior of the car! Another drawback to this, is that I have fought with noise in the radio for ever since moving the battery.

This annoyance is a small price to pay for performance of the big downpipe though!
My final design is as follows:

  • Ground Wire - 0/1 Gauge wire from battery to engine.
  • Ground Wire - 4 Gauge wire from engine to front frame rail
  • Power Wire - 4 Gauge wire from battery to 100 AMP breaker
  • Power Wire - 4 Gauge wire from breaker to starter
  • Power Wire - 4 Gauge wire from starter to alternator
  • Power Wire - 4 gauge wire from alternator to distribution block
  • I use a 100 AMP breaker in case a power wire shorts out and it is also a good storage system. You can just flip the breaker and all power is lost to the car. Some people have asked if the breaker trips when starting the car, and the answer is that it has never tripped, ever.

    Be sure to run the power wires next to each other and cross them over each other every foot. This keeps the EMI down. Mine come from the left side (facing the rear of the car), then go across the backseat, and then go down the right side of the car.

    I ran the main power wires through the firewall to the right of the clutch pedal and below the clutch master. Be sure to use some rubber grommets for the wires. (Available at a small hardware store)

    I attached the ground wire directly to the engine block near the starter. The preferred location is something much closer to the battery, but I was having major electrical issues before connecting to the block.

    In order to solder the 4 gauge connectors onto the wire you will need a propane torch, some solder flux and some solder.

    1. Apply some flux to the wire.
    2. Heat up the connector with the torch and fill it about 1/4 of the way up with solder.
    3. Put the wire into the connector and press the connector down with some big pliers. (The wire will still fall out so be careful)
    4. Heat up the connector again and solder the end of the connector. Once the connector and wire is hot enough, you will see the solder go into the wire.
    5. Put on some shrink wrap and heat it up with the torch to seal the connection between the wire and the terminal.
    This will ensure a good, solid connection.
    This process takes some time to perfect, but after 2-3 connectors you will become an expert!


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    Big Downpipe

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