Car Questions

Clear all

[Solved] Octane Booster Question


Topic starter

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!

This topic was modified 5 days ago by G.T.
6 Answers

Just go somewhere else and buy 91 octane gasoline.


Buy Premium.

You'll spend a fortune on octane booster otherwise.


Check out the 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


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


More cost effective to just use premium gas.


"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?