Kestas
Staff member
Good article. It's hard to justify paying 26% more for gasoline to get 1 to 3% better gas mileage.
I would have liked to see the actual test temperatures. The closest we get to this info is, "We performed acceleration runs, 200-mile fuel-economy loops at 75 mph, and dynamometer pulls, running each vehicle on two different fuels and completely draining the tanks in between. The differences likely would have been exaggerated by extreme summer heat, which exacerbates engine knock, but we sniffed out differences even with the engines huffing cool midwestern spring air."
This is a good read.
Various forum members state to use high (92) octane gas in a GDI in even a non - turbo engine . I have a Hyundai 2.4L non turbo GDI engine and have tried several tanks of high octane (92) gas in it : While the engine naturally has greater pep with the higher octane gas - my gas mileage is better with the 87 octane gas . Please explain the added benefit of using high octane gas in a GDI engine (i.e. less intake valve deposits , extended spark plug life , etc. ) ? Thanks in advance !
I tested my CX5, and 20-80mph pulls resulted in a difference of 0.2 seconds between 87 and 93 octane, FWIW. Also, one magazine tested the CX5 on regular 87 and premium 93, and noted that their instrumented testing of it showed no appreciable difference.All else being equal except the octane, it won’t any difference to deposits, spark plug life, or anything else. That being said, Top Tier>non-top tier, and some retailers do advertise their premium as having more detergents in their premium grade.
From the manual I saw online, they say “87 octane or higher” which hints at it being able to take advantage of the higher octane fuel. Will you notice a real world difference? Unlikely.
Since some high compression engines use fuel/timing to address issues with knocking, no one has long term studied octane vs performance vs fuel dilution vs engine longevity. I'll wager that premium might be beneficial in the long run...