Tow vehicles' engines

System

This discussion was created from comments split from: Tow Vehical MPG....

wizard1880

Don't want to derail this thread so this'll be my last post on the subject of turbo's / superchargers.

More and more modern vehicles come with them as they're great for increasing the mileage, keeping the same power but shrinking the displacement.  There's 2.0L 4-bangers making over 300 HP these days!  (check the new Volvo XC90)

The reasons most vehicle manufacturers stick with turbos is that it's taking energy (heat) that is normally wasted from the exhaust and converting it into usable power.  The variable-vane technology help keep lag to a minimum.  Superchargers rob power from the engine's crankshaft directly to spin it.  Plus you need lots of space in the engine bay to mount a supercharger.  This is not to say manufacturers avoid them--look at the new 2017 Audi Q7 3.0T -- supercharged only.  And some vehicles combine BOTH a turbo and supercharger (again look at the Volvo XC90)!

There is a move in the automotive world to upgrade all fuel octanes available (read here) as they provide great benefits for forced-induction (turbo/supercharger) vehicles....albeit at a higher fuel price.  Someday you'll be able to get >100 octane from the pump...!