Apologies if this was covered before, but I was watching yesterday’s episode of 5th Gear on BBC America (the one where they test the Toyota/Scion FT-86, Kia Sportage, and Tiff races a Lambo in the Lambo Cup), and saw a very interesting report on whether premium gasoline (petrol) produces more power than regular gas, at least for UK gas.
They tested shell v- power 98 ROM = 93 premium in the US, BP ultimate 97 RON ~ 91/92 premium in the US and 2 “regular” non premium gasolines. They tested the gas on a 2.0 turbo GTI and a dyno (rolling road for you Brits) and had rigs to switch between gas types w/o contaminating or having left over gas in the tank. The results were that the Shell v- premium made about 5 HP more on the dyno to the wheels. I find that a significant result just by using good gas. See a screen shot pic of results. I have no idea if the gas sold in the US would have a similar formulation, but I would hope so. Esso (Exxon/Mobile in the US) premuim gas also had close to a 5 HP advantage over regular gas.
Back when I had a turbo Subaru I could swear that I felt the car ran stronger on shell V-power, but had no proof. I’ve been using v-power since. I theorize that premium gas has a greater effect on turbocharged cars as the cars computer can slightly adjust timing and boost to make more power. As our X3’s are all turbo now (and the X35 since 2011), I figured to pass this along. I know I’ll continue to use shell v-power 93 (US RM/2) on all my cars.