What value Octane?

Shovelman · 12-29-2018, 05:59 AM

2017 230i with no mods

Is designed to run on 89 octane. If it is run on lower octane it protects itself from preignition by retarding the timing, reducing power.

So if it is run on higher octane does it advance the timing and produce more power?

Of course there is more to it than just octane and power, but without thread jacking please, what about the octane/power question?

msej449 · 12-29-2018, 06:23 AM

Over here in the UK, BP and Shell offer a 'super' car fuel that's 98-99 UK Octane (92-93 US Octane). I get Shell V-Power nitro+ mainly for the detergent cleaning additives, as opposed to any performance gain. As I'm keeping my M235i Convertible for a few years, and I don't do a high mileage, I'm happy to pay the premium if it does anything to help longer-term engine health. I'd say that subjectively, I've not noticed a significant difference in performance between the lower and higher octane fuels in driving on public roads, so if it was a lease car I was handing back after, say, 3 years, I probably wouldn't bother paying the extra for the V-Power.

Climate Changer · 12-29-2018, 07:55 AM

My wife and I leased about 10 bmws throughout the years. I religiously put 93 octane in my cars even though it requires 89. My wife puts the cheapest brand and octane here which is 87 in her cars. I honestly cannot tell the difference in performance between the two octanes I don't even hear any engine knocking noise as they state might happen with 87.

I will still use 93 regardless. We only kept our cars for three years so I cannot comment on the longevity of lower octane on the engine.

I would love if someone can explain this in detail.

Maynard · 12-29-2018, 09:21 AM

This has really been covered to death in several other forums, complete with very detailed tech info; search function is your friend. Summary is something like 'it probably won't seriously hurt engine to run lower than recommended octane, but computer will pull boost/timing so you lose some power'. Less info and more mixed opinions on benefits of higher-than-recc'd octane in stock config (clearly beneficial for tunes); no idea if a 230 can use extra octane, but possible that midrange power would improve. Using a 'Top Tier' gasoline seems to be the most meaningful part of this, since the improved additives likely do make a difference long term; and using at least the recommended octane, since the potential for engine damage would overwhelm any potential savings.

USA-RET · 12-29-2018, 09:52 AM

Quote:

Originally Posted by Maynard

This has really been covered to death in several other forums, complete with very detailed tech info; search function is your friend. Summary is something like 'it probably won't seriously hurt engine to run lower than recommended octane, but computer will pull boost/timing so you lose some power'. Less info and more mixed opinions on benefits of higher-than-recc'd octane in stock config (clearly beneficial for tunes); no idea if a 230 can use extra octane, but possible that midrange power would improve. Using a 'Top Tier' gasoline seems to be the most meaningful part of this, since the improved additives likely do make a difference long term; and using at least the recommended octane, since the potential for engine damage would overwhelm any potential savings.

^THIS

tennisfreak · 12-29-2018, 11:15 AM

I almost always use top tier and try to stick to Shell v power nitro.

Recently I was in a hurry and filled up with Kroger 93 octane.
There was a noticeable difference in responsiveness and power.

I almost thought there was something wrong with my dinan tune. I also considered maybe I didn't get true 93 octane.

Next tank I went back to Shell 93 and the power felt normal again.

///M Houbi · 12-29-2018, 11:34 AM

Stock DME of BMW's cannot sense anything more than 98ROZ. If you put in V-Power (100ROZ) then it will not give youe more power than the 98ROZ fuel, but you'll have cleaner combustion and the additives will help the motors longevity.

Personally i did V-Power 100 for over 12years in my E46 330Ci. It had a custom tune which could actually sense the 100 octane and make a something out of it.

In my M2 Competition also only V-Power 100 plus 30ml of Payback's Fuel Optimiser each fill.

morphomeman · 12-29-2018, 11:36 AM

With modern engines, lower octane will not induce knock, but the fuel management system will dial back the settings and you are likely to get worse performance and mileage. The savings from the lower price will then be offset by a combination of lower power and more fuel consumption. Keep it at 93. 91 will also work well, but hard to get in the NYC area.

ScottAndrew · 12-29-2018, 07:00 PM

I noticed the difference in power output, responsiveness and engine noise between 95 RON and 100 RON in my E46. 95 was fine but the engine just sounded happier and bigger-chested with the rocket fuel, and returned 5% better gasmileage.

In a 230i, not much difference. I think it's there, but I may just be convincing myself. It's hard to go near full throttle even with this car in gridlock, 20 mph traffic, the plethora of instant and average speed cameras, the other 38m idiots on the road, etc. Joining a (camera-monitored) motorway is about the only time you can do it, but flat out from 40-70 mph the difference caused by the fuels is going to be a long way sub 0.1 sec for that increment, which takes around 3 sec.

babaikram · 12-31-2018, 06:30 AM

Costco premium diesel makes significant difference to the performance of 520d especially at the mid range mph. The difference is night and day.

wichitagreg · 12-31-2018, 09:20 AM

The OP asked this question: "So if it is run on higher octane does it advance the timing and produce more power? "

The answer is No.

Unless: the tune allows it and I doubt it does. It would mean the tune wants the higher octain and is always dialing it back to compensate. There "may" be ion knock sensing (ala Harley Davidson) that will sense impending knock and retard the timing for a few milliseconds....this you can feel.

In my opinion, running higher octane fuel where not required will result in more combustion chamber deposits.

You should run the lowest octane fuel you motor is designed (and tuned) to run on.

dradernh · 12-31-2018, 09:33 AM

Quote:

Originally Posted by wichitagreg

In my opinion, running higher octane fuel where not required will result in more combustion chamber deposits.

You should run the lowest octane fuel you motor is designed (and tuned) to run on.

Do you know which octane that is for the six-cylinder 2 series cars - 91 or 93?

aerobod · 12-31-2018, 11:25 AM

Quote:

Originally Posted by dradernh

Do you know which octane that is for the six-cylinder 2 series cars - 91 or 93?

You should have a sticker on your fuel door. For our Canadian 2017 M240i it is 91 AKI (RON/2+MON/2)

morphomeman · 12-31-2018, 12:35 PM

93 cannot harm an engine designed to run on 91. In most markets, either 91 or 93 is available, not both. Use the fuel that is available in your area.

dradernh · 12-31-2018, 07:46 PM

Quote:

Originally Posted by aerobod

You should have a sticker on your fuel door. For our Canadian 2017 M240i it is 91 AKI (RON/2+MON/2)

Thanks - I see that I've got the same sticker on my fuel door. I've put Shell V-Power NiTRO+ 93 octane in the car since I got it.

jules_78th · 12-31-2018, 08:48 PM

I have a 2019 m240i. Ive been putting 91 and once a month 94. Its ok to mix it up right?

Plynth2697 · 12-31-2018, 10:02 PM

Quote:

Originally Posted by babaikram

Costco premium diesel makes significant difference to the performance of 520d especially at the mid range mph. The difference is night and day.

Costco is a "top tier" gasoline so I'm not surprised at your results. For those unacquainted, you might find this worthwhile to read:

https://www.consumerreports.org/car-...h-extra-price/

Maynard · 01-01-2019, 11:29 AM

Quote:

Originally Posted by jules_78th

I have a 2019 m240i. Ive been putting 91 and once a month 94. Its ok to mix it up right?

Correct, no problems mixing. If Canada uses the same metric as the US (ron+mon/2) either should be fine. Quick i'net grab looks like that is the case, but if those are euro-style octane ratings (just ron) then the 91 is too low and 94 is right about at the minimum. Should say right on the pumps.

You are probably better off adding a routine cleaning rather than occasional high-test, unless it is explicitly a better additive package, like for VPower (I use Techron every 5k; can't get Shell locally).

Sportstick · 01-01-2019, 12:02 PM

Quote:

Originally Posted by Maynard

Correct, no problems mixing. If Canada uses the same metric as the US (ron+mon/2) either should be fine. Quick i'net grab looks like that is the case, but if those are euro-style octane ratings (just ron) then the 91 is too low and 94 is right about at the minimum. Should say right on the pumps.

You are probably better off adding a routine cleaning rather than occasional high-test, unless it is explicitly a better additive package, like for VPower (I use Techron every 5k; can't get Shell locally).

Careful on frequency of Techron. Don't use more than twice per oil change. It has a deteriorating effect on the oil. Best to use it just before going in for an oil change.

dradernh · 01-01-2019, 02:33 PM

Quote:

Originally Posted by Plynth2697

Costco is a "top tier" gasoline so I'm not surprised at your results. For those unacquainted, you might find this worthwhile to read:

https://www.consumerreports.org/car-...h-extra-price/

More here: https://www.toptiergas.com/, including the current list of brands licensed to use the Top Tier logo.

Quote:

Originally Posted by Sportstick

Careful on frequency of Techron. Don't use more than twice per oil change. It has a deteriorating effect on the oil. Best to use it just before going in for an oil change.

I've noticed that BMW recommends using it every 3K, so roughly 3X per oil change. Note that BMW suggests using its fuel system cleaner if you're not using a Top Tier gasoline exclusively. That seems to be the principal focus of the product.

What information have you come across regarding its effect upon the engine oil? Causing premature engine oil degradation is the last I want to see happen. As it is, I've used the BMW-branded product once - that was at 650 miles before an oil change.

Sportstick · 01-01-2019, 02:43 PM

Quote:

Originally Posted by dradernh

More here: https://www.toptiergas.com/, including the current list of brands licensed to use the Top Tier logo.

I've noticed that BMW recommends using it every 3K, so roughly 3X per oil change. Note that BMW suggests using its fuel system cleaner if you're not using a Top Tier gasoline exclusively. That seems to be the principal focus of the product.

What information have you come across regarding its effect upon the engine oil? Causing premature engine oil degradation is the last I want to see happen. As it is, I've used the BMW-branded product once - that was at 650 miles before an oil change.

I would be interested to see the source for the 3k recommendation. When I had my prior car, MB C Class, Techron was also a topic of conversation on MBWorld. A gentleman there from South Africa worked in the oil industry and was quite expert. He produced information about the effect of an excellent fuel system cleaner, such as Techron (which he recommended, with no business connection), but with caution about the effect of the fuel/Techron blend on the cylinder wall washing into the oil and causing detrioration.

With a Top Tier fuel, with that high level detergent package, every 3k miles seems excessive based on what I've learned. In the absence of Chevron fuel, with small doses of Techron already blended in, I am using Techron once per oil change, and timing it to very empty (reserve light on) and reflll the tank before the oil service visit. I do exclusively use Top Tier fuel, such as Costco, which exceeds the standard significantly.

3rdcoast228i · 01-01-2019, 05:29 PM

The BMW stuff is rebranded Techron.

The Techron comes in different concentrations in the same size bottle. So pay attention to that.

Techron is good stuff, used correctly you shouldn't have oil contamination problems. Use the correct amount for your tank and don't use too often.

If you really want to make sure the fuel system is clean, double the concentration and run that out right before an oil change.

12-29-2018, 05:59 AM	#1
Shovelman Lieutenant 244 Rep 527 Posts Drives: 2017 230i Join Date: Jan 2017 Location: Michigan iTrader: (0)	What value Octane? 2017 230i with no mods Is designed to run on 89 octane. If it is run on lower octane it protects itself from preignition by retarding the timing, reducing power. So if it is run on higher octane does it advance the timing and produce more power? Of course there is more to it than just octane and power, but without thread jacking please, what about the octane/power question?
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12-29-2018, 06:23 AM	#2
msej449 msej449 514 Rep 717 Posts Drives: M235i Convertible +LSD 2016 Join Date: Nov 2013 Location: South Coast UK & Swiss Alps iTrader: (0) Garage List 2023 Peugeot e208 GT [0.00] 2016 BMW M235i Conv ... [0.00]	Over here in the UK, BP and Shell offer a 'super' car fuel that's 98-99 UK Octane (92-93 US Octane). I get Shell V-Power nitro+ mainly for the detergent cleaning additives, as opposed to any performance gain. As I'm keeping my M235i Convertible for a few years, and I don't do a high mileage, I'm happy to pay the premium if it does anything to help longer-term engine health. I'd say that subjectively, I've not noticed a significant difference in performance between the lower and higher octane fuels in driving on public roads, so if it was a lease car I was handing back after, say, 3 years, I probably wouldn't bother paying the extra for the V-Power. __________________ 2016 M235i Convertible Estoril Blue & Oyster 2023 Peugeot e-208 GT (electric)
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12-29-2018, 07:55 AM	#3
Climate Changer Second Lieutenant 109 Rep 278 Posts Drives: 2018 230i xdrive convertible Join Date: Oct 2018 Location: New York iTrader: (0) Garage List 2018 230i xdrive co ... [0.00] 2019 x3 [0.00]	My wife and I leased about 10 bmws throughout the years. I religiously put 93 octane in my cars even though it requires 89. My wife puts the cheapest brand and octane here which is 87 in her cars. I honestly cannot tell the difference in performance between the two octanes I don't even hear any engine knocking noise as they state might happen with 87. I will still use 93 regardless. We only kept our cars for three years so I cannot comment on the longevity of lower octane on the engine. I would love if someone can explain this in detail.
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12-29-2018, 09:21 AM	#4
Maynard Colonel 3848 Rep 2,873 Posts Drives: 228iX & M2C Join Date: Mar 2016 Location: Upstate NY iTrader: (1)	This has really been covered to death in several other forums, complete with very detailed tech info; search function is your friend. Summary is something like 'it probably won't seriously hurt engine to run lower than recommended octane, but computer will pull boost/timing so you lose some power'. Less info and more mixed opinions on benefits of higher-than-recc'd octane in stock config (clearly beneficial for tunes); no idea if a 230 can use extra octane, but possible that midrange power would improve. Using a 'Top Tier' gasoline seems to be the most meaningful part of this, since the improved additives likely do make a difference long term; and using at least the recommended octane, since the potential for engine damage would overwhelm any potential savings.
	Appreciate 0 Quote

12-29-2018, 11:15 AM	#6
tennisfreak Second Lieutenant 201 Rep 296 Posts Drives: M240i Join Date: Feb 2018 Location: DFW iTrader: (0)	I almost always use top tier and try to stick to Shell v power nitro. Recently I was in a hurry and filled up with Kroger 93 octane. There was a noticeable difference in responsiveness and power. I almost thought there was something wrong with my dinan tune. I also considered maybe I didn't get true 93 octane. Next tank I went back to Shell 93 and the power felt normal again.
	Appreciate 0 Quote

12-29-2018, 11:34 AM	#7
///M Houbi Major 1655 Rep 1,237 Posts Drives: M2 Competition Join Date: May 2018 Location: Switzerland iTrader: (0) Garage List 2019 M2 Competition [0.00] 2003 E46 330Ci [0.00]	Stock DME of BMW's cannot sense anything more than 98ROZ. If you put in V-Power (100ROZ) then it will not give youe more power than the 98ROZ fuel, but you'll have cleaner combustion and the additives will help the motors longevity. Personally i did V-Power 100 for over 12years in my E46 330Ci. It had a custom tune which could actually sense the 100 octane and make a something out of it. In my M2 Competition also only V-Power 100 plus 30ml of Payback's Fuel Optimiser each fill. Attached Images __________________ Instagram \| M2 Competition Build Thread \| A tribute to my E46 330Ci
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12-29-2018, 11:36 AM	#8
morphomeman Major 593 Rep 1,219 Posts Drives: 2015 M235ix Join Date: May 2015 Location: United States iTrader: (1) Garage List 2016 BMW X3 [0.00] 2015 BMW M235ix [0.00]	With modern engines, lower octane will not induce knock, but the fuel management system will dial back the settings and you are likely to get worse performance and mileage. The savings from the lower price will then be offset by a combination of lower power and more fuel consumption. Keep it at 93. 91 will also work well, but hard to get in the NYC area.
	Appreciate 0 Quote

12-29-2018, 07:00 PM	#9
ScottAndrew Banned 374 Rep 520 Posts Drives: BMW 230i Join Date: Aug 2018 Location: Hampshire iTrader: (0)	I noticed the difference in power output, responsiveness and engine noise between 95 RON and 100 RON in my E46. 95 was fine but the engine just sounded happier and bigger-chested with the rocket fuel, and returned 5% better gasmileage. In a 230i, not much difference. I think it's there, but I may just be convincing myself. It's hard to go near full throttle even with this car in gridlock, 20 mph traffic, the plethora of instant and average speed cameras, the other 38m idiots on the road, etc. Joining a (camera-monitored) motorway is about the only time you can do it, but flat out from 40-70 mph the difference caused by the fuels is going to be a long way sub 0.1 sec for that increment, which takes around 3 sec.
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12-31-2018, 06:30 AM	#10
babaikram M6GCComp, Porsche Cayman S PDK, Peug 208 GT1 BPS 512 Rep 1,280 Posts Drives: . Join Date: May 2015 Location: England iTrader: (0)	Costco premium diesel makes significant difference to the performance of 520d especially at the mid range mph. The difference is night and day. __________________ Acceleration is heavenly
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12-31-2018, 09:20 AM	#11
wichitagreg Private 35 Rep 67 Posts Drives: 2016 M235i Cabriolet Join Date: Nov 2018 Location: Kerrville, TX iTrader: (0)	The OP asked this question: "So if it is run on higher octane does it advance the timing and produce more power? " The answer is No. Unless: the tune allows it and I doubt it does. It would mean the tune wants the higher octain and is always dialing it back to compensate. There "may" be ion knock sensing (ala Harley Davidson) that will sense impending knock and retard the timing for a few milliseconds....this you can feel. In my opinion, running higher octane fuel where not required will result in more combustion chamber deposits. You should run the lowest octane fuel you motor is designed (and tuned) to run on.
	Appreciate 0 Quote

12-31-2018, 12:35 PM	#14
morphomeman Major 593 Rep 1,219 Posts Drives: 2015 M235ix Join Date: May 2015 Location: United States iTrader: (1) Garage List 2016 BMW X3 [0.00] 2015 BMW M235ix [0.00]	93 cannot harm an engine designed to run on 91. In most markets, either 91 or 93 is available, not both. Use the fuel that is available in your area.
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12-31-2018, 08:48 PM	#16
jules_78th Private 28 Rep 62 Posts Drives: 2019 M240i Cabriolet Join Date: Sep 2018 Location: Toronto iTrader: (0)	I have a 2019 m240i. Ive been putting 91 and once a month 94. Its ok to mix it up right? Last edited by jules_78th; 12-31-2018 at 09:19 PM..
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01-01-2019, 05:29 PM	#22
3rdcoast228i Captain 225 Rep 610 Posts Drives: 2016 228i Msport Join Date: Apr 2017 Location: Texas iTrader: (0)	The BMW stuff is rebranded Techron. The Techron comes in different concentrations in the same size bottle. So pay attention to that. Techron is good stuff, used correctly you shouldn't have oil contamination problems. Use the correct amount for your tank and don't use too often. If you really want to make sure the fuel system is clean, double the concentration and run that out right before an oil change.
	Appreciate 0 Quote