Being very proud to be British this kinda gets my back up. Especially as the world together talks BHP, especially on the aftermarket and performance tuning circles!! Even the Americans take BHP. And car dealers still sell in BHP!
I believe the first measurements engine wise was just horse power HP equivalence but this evolved to BHP Brake-horsepower or scientifically as 'mechanical horsepower' (pinch yourself if you are falling to sleep 😴)
PS stands for the German word 'pferdestärke' or 'horse strength' but is a metric scale. BHP is approx 98.6% of this so 1PS = 0.986BHP. (We obviously breed better stronger horses in the 🇬🇧 lol).
The car market widely interchanges these figure. In the world of VAG the 2.0 TDI engine was most commonly designated 140PS and 170PS but referred to as 140 and 170BHP (Are you still awake?!?) The easy way to convert this is to drop 1 BHP for every 70PS, so a 140PS car is basically 138BHP! This is an approximation that is easily used.
Now, Kw or Kilowatt, introduced in the early 90's was an EU thing. It didn't catch on for about 10 years but even today while quoted in all brochures etc BHP is still the figures preferred. Now that we are seeing more hybrid technology etc it's becoming more popular.
Again using the 140PS or 138BHP engine, times the PS value by 0.7457 which gives approx 104.5 Kw.
Though to simplify things (stop yawning!!)
Times the Kw value by 1.32 to give BHP and 1.34 to give PS. And just drop 1BHP for every 70PS.
E.g. 104.5Kw engine is (104.5 * 1.34)= 140PS (-2)= 138BHP.
My car is a 180ps which basically is 177BHP Or a 134.3Kw engine.
Clear as mud. I need a drink!!