Colder the better and higher density typically goes along with colder temperatures. Of course the cold starts are not good on an engine (nor batteries, belts, and a slew of other car things) at all but if the question is purely about power then colder the better. Growing up in Alaska the coldest parts of the winter (-40 to -50 deg F) made for some serious bumps in power.
E92 M3 | Space Gray on Fox Red | M-DCT | CF Roof | RAC RG63 Wheels | Brembo 380mm BBK |
| Vorsteiner Ti Exhaust | Matte Black Grilles/Side Gills/Rear Emblem/Mirrors |
| Alekshop Back up Camera | GP Thunders | BMW Aluminum Pedals | Elite Angels |
| XPEL Full Front Wrap | Hardwired V1 | Interior Xenon Light Kit |