Improving a legend - weight cutting on an E46 M3

The BMW e46 M3 is one of the most popular cars for enthusiasts today. That zingy 3.2-litre 338bhp straight-six is wonderful, paired with a highly exploitable chassis, there are very few cars out there that can compete for pure driving feel. Some minor modifications and a weight cut make it a formidable challenger on road and track.

Deadweight Industries worked with grassroots enthusiasts from Piston Lab UK and racing teams to look at weight reduction options. We're particularly interested in value for money (£ per kg saved). As demonstrated by the table below, the cost of weight-reducing modifications can be quite astronomical.


Weight saving


£ per kg saved

Karbonius CSL carbon roof and install




SuperSprint exhaust backbox




SuperSprint 100 cell catalytic converter




Genuine CSL 19 inch wheels




Recaro Pole Position seats and mounts




Touge 500 - our medium-sized LiFePO4 battery

17kg £390 £26

Reducing the weight of the battery is nothing new. It has been used extensively in the latest BMW M and Porsche GT models, the downside has always been the cost. These units typically costing well over £1500 OEM. Aftermarket options up until now have been limited and can be just as expensive.

Thankfully we're here to provide a better value for money proposition. Touge 500, our medium-sized battery provides superior performance, at 18% of the weight of the OEM battery. At just 3.5kgs, it is more than 15kgs lighter than OEM. It also offers superior-tech at a cost significantly less than batteries from our competitors.