neomaxmaya

Hey guys,
my car gas tank lid has a tag for fuel type says 93 min.
Now in Ontario, Canada the premium gas is 91. where only Petro Canada offers 94 (ultra). however, its a bit far from my house to go there.
so I was wondering if it's OK to fill 91 instead. and would this affect the engine life span? can anyone shed some light on the difference of 91 vs 93 use. how is this used in the car? how does it affect the combustion?
Note that gas price is not my concern as much as the convenience of having a close gas station.
Thanks

vvrjrlaw

If my memory serves me the higher the octane the higher the mixture can be compressed ( by the piston) before ignition. In the old days of 105 octane use there wasn't a car that would preignite regardless of compression. You say a bit far but how far is your call. Is it far enough that you would take the chance of doing engine damage rather than going for it. In the USA 91 is mid grade and 92 is hi octane. I use the ultra 93 octane whenever possible ( which is all the time locally) because it is the highest pump grade available. The problem is the ethanol that goes into it as well. It doesn't burn as clean and is designed to supplement and deter preignition. The answer is not ethanol it's adding lead like the old days. IMHO. Good luck.

neomaxmaya

Well, Petro Canada is 10mins drive from my house and their washing station sucks! Vs. Shell is at the corner of my neighborhood (1min drive), and their washing station is way better plus AirMile reward program.
However, if using 91 will eventually damage the engine, then I rather drive the 10 mins and wash the car somewhere else.
Thanks for the advise bro

alexanish

Hello, I will be speaking behalf of my friend. He has 2014 CLS63 AMG Sport. apparently he used to fill up on Petro and ESSO and few kilometers after he was getting engine light on for some reasons. As soon as he tried Shell this problem went off. I personally use only shell for German cars and it its Japanese then petro.

neomaxmaya

Well, if your friend is filling less than Octane 91 then the engine will be damaged regardless which station he filled from.




I don't think I would take the chance of damaging my engine if AMG said minimum 93 then I wont screw with it.
Thanks for the feedback though.

alexanish

Well as I mention I use Shell V power for past 5 years and never had any issues. Good luck!

sick430

you guys are luck the best we have in California is 91. Also, what rating system is canada using? Are you looking at RON / MON / AKI?

neomaxmaya

Your question Sir have got me curious to learn more about this.
So as of Wikipedia, Canada and most of US states use AKI rating system.
Which means petro Canada 94 is higher than Shell 91.
Therefore, I'll be sticking to petro Canada and will not take the chance and cause knocking issues with my M156.
http://en.m.wikipedia.org/wiki/Octane_rating
Thanks all for the feedback