Trunk-mount battery for AutoX?

[Bionic]

Does anyone know what requirements have to be met for a trunk-mounted battery to be legal for AutoX events?

External cut-off switch? vent? etc

[SteveW]

From the 2008 SCCA Rulebook

Page 27, Section 3.3.3 Vehicle Safety Inspections (basically tech inspection):

Quote:

17) Any wet-cell battery moved from the manufacturer’s original
location shall be in a non-conductive marine-type container or
equivalent, and the hot terminal shall be insulated. All batteries
(on-board power supplies) shall be attached securely to the
frame or chassis structure independent of the marine-type
container. NOTE: This will allow the use of gel cell or dry
cell (AGM) batteries without a non-conductive marine-type
container where applicable.

Page 77, Section 14.9 Street Touring Electrical (SP has the same rule)

Quote:

A. The make, model number, and size of the battery may be
changed but not its voltage. Relocation of the battery or batteries
is permitted but not into the passenger compartment. If the battery
is relocated and the original battery tray can be removed by
simply unbolting it, the tray may be removed, or relocated with
the battery. Holes may be drilled for mounting or passage of
cables. Longer cables may be substituted to permit relocation.
The number of battery or batteries may not be changed from
stock. The area behind the rearmost seat is not considered to be
within the passenger compartment.

Looks to me like a gel-cell battery securely mounted in the trunk would be fine. I don't see any requirements for cut-off switches or vents so none should be needed.

I assume this is to improve weight distribution, right? Why not just put a lawnmower battery in the stock location instead of a heavy one in the trunk with all that heavy cable running back up front?

[Bionic]

hmm, guess I could just drop in a smaller battery on event days,
and back to 'ol Bessy for daily driving...

[Got_SRT-4?]

Quote: Originally Posted by SteveW

Why not just put a lawnmower battery in the stock location instead of a heavy one in the trunk with all that heavy cable running back up front?

Does a lawnmower batter have enough juice to crank the car? I've thought about getting a smaller battery, but then I would probably need to get corner balanced again. Unfortunately the guy I knew with scales sold them to buy new wheels and tires this year. So now I got to find somewhere else to adjust the corner balance if I do any weight reduction/repositioning.

[SteveW]

Not sure about the 2.4l but I used one in my 1st gen STS car. Worked great and I just left it in all season long. Of course, you wouldn't want to be leaving the doors open long or have some other draw going on but everything's a compromise.

I don't remember exactly how big it was but it wasn't quite as small as a motorcycle battery and it was at least half the weight of the standard battery. It said "Lawn and Garden" on the side, lol.

Try it and let us know...