Which part secures your battery?

 

Currently I have a side wedge that is adjustable to the size of the battery but saw this above which looks like it holds the battery down.

 

A wedge will not hold a battery at all if you have a significant impact or off. AFAIK the hold-down you pictured is the standard one.

 

You are probably right but real oem does not show the hold down for 2005 vert. Only the wedge. I believe the wedge clamps it down.

 

My 05 330xi has the hold down shown in post #1. My 06 330ci vert does not, rather it uses a clamp with long bolts (sorry, hard to explain).

 

Yeah I think that is what I have. A single clamp with a very long bolt that screws in to hold it in place.

 

Is your battery located in the trunk? Because batteries under the hood have that L shaped bracket with long bolts... If its under the hood, then this part will not fit

 

Yes in the trunk. I have seen other e46 m’s with the L shaped bracket and others without it. Real oem does not indicate that the Al bracket is for m’s but I have seen some with it and made me wonder.

 

This is used for sedan, coupe, touring and compact. It is not used for the convertible.

 

The cabriolets use a different hold down system over that of the sedan counterparts.
Since the battery tray is part of a floating box (cabrio's flex a lot) and the older more conventional long bolt/clamp is utilized. To retain the battery inside of the floating box.

The part you show would negate any ability of the tray to "float."

RealOEM.com - Online BMW Parts Catalog

BMW parts 3' E46 M3 battery holder and mounting parts

www.realoem.com

 

Great info thank you. That explains it.