My question deals with a 2001 BMW 525i, automatic transmission, witb about 275k miles on it. My job is about to offer gasoline to employees at cost price, but it's just regular unleaded gasoline. My question is since my car requires 91octane or better, is an octane booster ok to use on the regular to get that gasoline up to spec with my car, and if so, what additive do you recommend? Thanks!
Just go somewhere else and buy 91 octane gasoline.
Buy Premium.
You'll spend a fortune on octane booster otherwise.
Check out the race-gas.com calculator:
Race gas original 87 base octane - desired octane 91
2 ounces of race gas added per gallon of 87 octane = boosts octane to 91
Race Gas concentrate 32oz price: $32.49 (plus your state tax rate?) = Approximately $1.02+ an ounce
20 gallons of 87 octane + 40 ounces of race gas = Not worth the price
More cost effective to just use premium gas.
You can use booster but read the direction it requires quite a bit of them to boost up say 20 gallons of gasoline you might find it's cheaper to actually buy the higher test
"my car requires 91octane or better"
You did not indicate what country you re in. As far as I know, 525i requires the _European_ 92 Octane. Off the top of my head, the European 92 Octane approximately equals the US 87 Octane = the US regular gas.
Do you have any literature that US octane rating system is different from EU octane rating?
"Do you have any literature"
Not really. Read it many times in many sources, but all those sources were in Russian, sorry.
However the English Wiki also says:
"Because of the 8 to 12 octane number difference between RON and MON noted above, the AKI (Anti-Knock Index) shown in Canada and the United States is 4 to 6 octane numbers lower than elsewhere in the world for the same fuel."
(RON and MON being different octane index measuring methods used in different countries)
https://en.wikipedia.org/wiki/Octane_rating
Interesting. I did not know that. Thanks.
With octane boosters you need 10 points to equal 1 number. If your using 87 and want to boost to 91 you'll need a 4 number increase or 40 points. A lot of boosters only increase 2 to 5 points and cost 3.99 to 7.99 a bottle. There are some out there that increase by 10 points or 1 number but cost 11 to 20 dollars. Vp fuel makes a booster. Let's not for get Mmt which is in alot of boosters can hurt emissions system in large quantities
