Did you know that the BMW 840ci, 540i and 740i have an embarrassing 0-60MPH acceleration of somewhere between 7.1 and 7.4 seconds? It's a bit sad that they accelerate no quicker than a 118i M-Sport with the tiddly 4-pot engine!

My E31 840ci does it in 6 seconds - and this video is all about the things that increase performance, and those that completely messes up engine performance!

This is Part 1 of a three part series - today we look at popular upgrades that LOSE power!

Timm's store: https://www.amazon.co.uk/shop/timmsbm...