Originally Posted by CXTKRS1
Their is a small chance that residue can build up if the fuel is not completely burnt but beyond that no harm is going to come to the engine. You will be pissing away a few bucks everytime you fill up though.  |
This has been addressed before on here I believe. I pretty much agree with that, but it can be a little more than that. When I was younger I borrowed my Dads new truck, drove it for awhile, and to show my appreciation filled it with 93 octane (though the manufacturer suggest 87). He was pissed, stating "Doing that doing that would cause his truck to need to continually need to use that expensive gas". Now a few fill ups is not going to do that, but doing it continuously can. Higher octane gas is meant to be a slower more controlled burn for higher heat and compression engines to stave off detonation. Engines designed to run on lower octane will not completely burn the higher octane and it will saturate any carbon deposits you may have. Now if you have a car designed to run on low grade but it knocks/pings then high octane will help it not to. Here's a nice little article.
http://www.state.mn.us/mn/externalDo...ctaneFacts.pdf