[Etch]

I've been driving my f22 for 2 years and have only used 89 octane and have no knocking or any other issues, 89 is perfectly fine.

[Maynard]

'no knocking' at best means you don't hear it or identify it. Could be you are getting some, but not realizing it (= big $$$ damage by 60k miles), or it could mean that your car has properly caught it and is pulling timing and boost to prevent more detonation (= you turned a BMW into a Toyota, and got to save $3 in fuel).

No stopping some from pursuing this rather unwise attempt to save trivial amounts of money, but the overwhelming majority will recognize that these cars can use all the octane they can get, and will reward with increased performance and reduced maintenance problems. To me, the paltry savings would not even be worth the time I'd need to be driving a loaner around - even if they paid for the engine repairs for free - but that performance is why I bought this car. If you just want an economical car w/ a roundel on the front, there are certainly cheaper options....

[tripitz]

Originally Posted by Maynard

'no knocking' at best means you don't hear it or identify it. Could be you are getting some, but not realizing it (= big $$$ damage by 60k miles), or it could mean that your car has properly caught it and is pulling timing and boost to prevent more detonation (= you turned a BMW into a Toyota, and got to save $3 in fuel).

No stopping some from pursuing this rather unwise attempt to save trivial amounts of money, but the overwhelming majority will recognize that these cars can use all the octane they can get, and will reward with increased performance and reduced maintenance problems. To me, the paltry savings would not even be worth the time I'd need to be driving a loaner around - even if they paid for the engine repairs for free - but that performance is why I bought this car. If you just want an economical car w/ a roundel on the front, there are certainly cheaper options....

Following guidelines is not "unwise"; that's why the manufacturers put them there. In fact, often people put in higher octane gas in normal cars than needed and it's actually worse for the car. In this case, the engine management system is going to lower boost and retard timing so to minimize/eliminate knock. There is a small drop in horsepower as a result of this (I think car and driver did a test like this with an A4 on a dyno). It's a personal choice; it doesn't damage/destroy the car.

This is also why aftermarket tunes can "unlock" so much power; they are effectively taking away some of the tolerances BMW engineered in the car. Most tunes require 91 if not 93.

For the record, I put 93 in I like my car at max boost/power.

[Maynard]

Sorry, but I will stand by my assessment that it is unwise to spend the extra money on even a 228/30, let alone a 235/40, and then neuter the performance, while playing brinksmanship with some extra-expensive engine internals. Those 'guidelines' don't recommend 89 octane, they say it is the lowest safe to use. Like, you are stuck in the middle of Timbuktu and they are out of premium; not like you want to brag to your uncle about how little you spent on a tank of gas. I don't know why this brand of 'I'm smarter than everyone else' keeps rearing its head around here (its a BMW fan page - we all spent an extra 10-20 grand on the car, another 20 cents per gallon is not an issue to enjoy that potential).

And higher octane is never worse for the car (that I know of), just a waste of money in those cars that aren't ready to use it.

[nikman011]

At least (Shell, and once Sunoco) 93, always, (have yet to encounter a situation where I couldn't get 93) .......... spent $54Gs on this car that I fill up once a week, so roughly $210 extra a year, ...... chump change, even if it were only for piece of mind it is money well spent.

PS: I don't know sh!t about cars other than how to change brakes

[Sportstick]

Originally Posted by Maynard

Sorry, but I will stand by my assessment that it is unwise to spend the extra money on even a 228/30, let alone a 235/40, and then neuter the performance, while playing brinksmanship with some extra-expensive engine internals. Those 'guidelines' don't recommend 89 octane, they say it is the lowest safe to use. Like, you are stuck in the middle of Nevada and they are out of premium; not like you want to brag to your uncle about how little you spent on a tank of gas. I don't know why this brand of 'I'm smarter than everyone else' keeps rearing its head around here (its a BMW fan page - we all spent an extra 10-20 grand on the car, another 20 cents per gallon is not an issue to enjoy that potential).

And higher octane is never worse for the car (that I know of), just a waste of money in those cars that aren't ready to use it.

Completely agree, but take a bit of umbrage at the Nevada reference....plenty of premium around here, and even good frequency of Chevron, so no extra bottles of Techron needed!

[Maynard]

FTFY - didn't mean to diss the 'speeder's state' , especially for a fellow 228 lover. I guess out there, Valencia is actually sort of a sleeper/camo color, huh?

[Sportstick]

Originally Posted by Maynard

FTFY - didn't mean to diss the 'speeder's state' , especially for a fellow 228 lover. I guess out there, Valencia is actually sort of a sleeper/camo color, huh?

Expecting a post from someone from Mali next!

Actually, the VO 2 Series is in storage back in Michigan where we are most of the year. Out here, considering heat rejection, I have a white 330 GT as the "family car". Looking forward to disconnecting the CTEK and rolling the 2 off the tire savers in early April! But, yes, I think if/when we make this permanent, the 2 will blend in quite well! Even the mountains are Valencia over Oyster!

[Maynard]

You know you are a true addict when you describe the landscape as Valencia over Oyster Is that you halfway up the Oyster section?

[Sportstick]

Originally Posted by Maynard

You know you are a true addict when you describe the landscape as Valencia over Oyster Is that you halfway up the Oyster section?

Nope...that's me behind the camera! I only ate a "regular" breakfast that day...not "premium", so I wasn't sure I was up for the climb (he said smoothly transitioning back to the thread topic!)

[harma24]

Originally Posted by Maynard

(= big $$$ damage by 60k miles)...

will reward with increased performance and reduced maintenance problems.

Originally Posted by Maynard

Those 'guidelines' don't recommend 89 octane, they say it is the lowest safe to use.

Correct, it is SAFE to use. As in, it will not cause the engine to fail at 60K miles. There's a reason why they cut it off at 89 octane and not 87. Note that the manual also clearly states that using certain types of fuels / fuel additives WILL cause engine damage (leaded, metallic additives, high ethanol content or other types of alcohol). Also please note that nowhere in the manual does it state that using 89 octane will cause engine damage. Do you honestly think BMW would open themselves up to the liability of engine failures while using a fuel grade that they say is acceptable for use in the car???

It's not about the cost. I fill up my car twice a week, with a premium of $0.15 for 93 vs. 89. That comes out to be ~$12/month. For most people on this forum who drive far less than I do, the cost should not be an issue. I am also not advocating that we should be using 89 octane on a regular basis; BMW recommends 93 for a reason. However, that's not the point.


Please stop disseminating false information that using 89 octane will destroy the engine!

[CE750Jockey]

Originally Posted by Sportstick

Nope...that's me behind the camera! I only ate a "regular" breakfast that day...not "premium", so I wasn't sure I was up for the climb (he said smoothly transitioning back to the thread topic!)

'stick, we got it after the first picture. You like Vegas. No need to post it twice to rub it in to those us us left behind in the frozen tundra.

[Luddy]

I am in the camp of just get premium fuel. The cars are already expensive. You probably aren't using the savings between 91/93 and 89 to make payments. Why risk the potential of issues by getting 89 all the time? Also, it is almost impossible to find definitive proof either way on this because by 60k miles so many other variables have been introduced.

[nikman011]

Love Octane threads!

[MichaelL]

Originally Posted by Luddy

I am in the camp of just get premium fuel. The cars are already expensive. You probably aren't using the savings between 91/93 and 89 to make payments. Why risk the potential of issues by getting 89 all the time? Also, it is almost impossible to find definitive proof either way on this because by 60k miles so many other variables have been introduced.

I agree. Just buy premium fuel and be done with it...

[aerostar]

Lol I know the manual states "Minimum 89". It says right below this that using 89 may cause engine knock.

I don't know about you guys but I've never heard of engine knock *being okay*.

Fuck that. Use 91+.

[Maynard]

Originally Posted by harma24

Please stop disseminating false information that using 89 octane will destroy the engine!

Lighten up guy - Don't get your emoji in a knot. I'm not saying this, and sorry to offend. I have tremendous respect for these engines, and don't mean to come off as saying they'll grenade at 60001 miles, even on crap fuel. I hope they are smart and flexible enough to just pull timing/boost and avoid knock (was actually shocked that they got obvious knocking with an Audi, even at 87 octane).

First, I'm saying it is just plain stupid to pay all the premium $$$ for a performance car, and then neuter that performance with lower grade fuel, especially to save a few bucks.

Second, I'm saying that it is risking some fairly expensive costs to use cheap fuel ALL THE TIME, and especially IF YOU ARE GETTING KNOCKING (and you really might not notice it, even if you think you would). My comment was about knock, not just using 89 octane, and I'll stand by it (they don't come w/ a 100k mile warranty, do they?).

[BEM-S4]

Originally Posted by Maynard

Lighten up guy - Don't get your emoji in a knot. I'm not saying this, and sorry to offend. I have tremendous respect for these engines, and don't mean to come off as saying they'll grenade at 60001 miles, even on crap fuel. I hope they are smart and flexible enough to just pull timing/boost and avoid knock (was actually shocked that they got obvious knocking with an Audi, even at 87 octane).

First, I'm saying it is just plain stupid to pay all the premium $$$ for a performance car, and then neuter that performance with lower grade fuel, especially to save a few bucks.

Second, I'm saying that it is risking some fairly expensive costs to use cheap fuel ALL THE TIME, and especially IF YOU ARE GETTING KNOCKING (and you really might not notice it, even if you think you would). My comment was about knock, not just using 89 octane, and I'll stand by it (they don't come w/ a 100k mile warranty, do they?).

Don't get me wrong $ is $ but how much could we possibly be talking about saving, a couple of hundred per year max?

Highest octane = cheap peace of mind.

[harma24]

Originally Posted by aerostar

Lol I know the manual states "Minimum 89". It says right below this that using 89 may cause engine knock.

You're right, it does. But you missed the rest of the statement. To quote the manual:

If you use gasoline with this minimum AKI Rating, the engine may produce knocking sounds when starting at high outside temperatures.
This has no effect on the engine life.

Originally Posted by BEM-S4

Don't get me wrong $ is $ but how much could we possibly be talking about saving, a couple of hundred per year max?

I drive ~26k miles/year. As I noted above, I fill up 2x per week, averaging a bit over 10 gallons per fill-up. With a premium of $0.15 for 93 over 89, this is ~$1.50/fill-up, ~$3/week, or $156/year. For those of you who drive around 12k miles/year, you'll spend an extra $75.

[aerostar]

Originally Posted by harma24

You're right, it does. But you missed the rest of the statement. To quote the manual:

If you use gasoline with this minimum AKI Rating, the engine may produce knocking sounds when starting at high outside temperatures.
This has no effect on the engine life.

I drive ~26k miles/year. As I noted above, I fill up 2x per week, averaging a bit over 10 gallons per fill-up. With a premium of $0.15 for 93 over 89, this is ~$1.50/fill-up, ~$3/week, or $156/year. For those of you who drive around 12k miles/year, you'll spend an extra $75.

I didn't miss that statement.

My point was, in what world is engine knock okay?

Please find me instances where it's actually okay.

You realize they only write shit in these manuals to cover their ass for the warranty period. They don't give a shit about what happens after.

[BEM-S4]

Right - thanks for doing the math. So your average driver we are talking $100 per year, $500 over a 5-year period. That's 1% if the price of the car, seems like very little money for better safe than sorry.

[BMWnerd2023]

if you go to https://www.bmwusa.com/owners-manuals.html and enter your VIN, you will access a digital manual for your exact car model. My 228i xdrive allows to use min 87 but BMW recommends 91 (see attached screenshot). So yes, you can use regular without any damage to your vehicle if the minimum recommended fuel is 87. If min is 89, then do not use anything below it. As someone pointed out- performance will likely drop if you use min recommended instead of 91 or 93. M models will likely need min 89, but again, just check your car's manual!

Cheers,
BMW nerd