ECU inquiry regarding timing adaptation

[Kizzu]

Is it true that our ecu (MSV80) adapts the timing according to the octane level?
I know this question is a bit far fetched but any information would be of great help

[TheSt|G]

Originally Posted by Kizzu

Is it true that our ecu (MSV80) adapts the timing according to the octane level?
I know this question is a bit far fetched but any information would be of great help

Yes, it does.

[128Convertibleguy]

Originally Posted by Kizzu

Is it true that our ecu (MSV80) adapts the timing according to the octane level?
I know this question is a bit far fetched but any information would be of great help

It doesn't work off octane level directly. Typically it's done by a "knock sensor", screwed to the side of the engine. That senses the first sign of knock, before it's apparent to you, and adjusts the timing to make it go away.

[Kizzu]

Originally Posted by TheSt|G

Yes, it does.

Originally Posted by 128Convertibleguy

It doesn't work off octane level directly. Typically it's done by a "knock sensor", screwed to the side of the engine. That senses the first sign of knock, before it's apparent to you, and adjusts the timing to make it go away.

and if you don't mind, is the change in BHP significant when running 99 octane compared to when running 85-93 octane or it's just minimal?

[Dackelone]

Originally Posted by Kizzu

and if you don't mind, is the change in BHP significant when running 99 octane compared to when running 85-93 octane or it's just minimal?

Well... it takes the computer about 400 kms to adapt... So... IF you fed your engine that higher fuel octane, yes it would make slightly more power, once the DME adapts.

[Kizzu]

Originally Posted by Dackelone

Well... it takes the computer about 400 kms to adapt... So... IF you fed your engine that higher fuel octane, yes it would make slightly more power, once the DME adapts.

I asked as they told me that the type of fuel feeding the car can vary up to 15bhp and I am very dubious about this

[flinchy]

It wont make more power past 93aki

It adapts down from the maximum, not up

[Kizzu]

Originally Posted by flinchy

It wont make more power past 93aki

It adapts down from the maximum, not up

And what does that mean in simplified words ?

[tuphdc]

Originally Posted by Kizzu

And what does that mean in simplified words ?

the ecu will not adjust for octane over 93

[Kizzu]

Therefore this means that 93 octane and 99 octane level will give me the same power?

[JimD]

The way the engine adapts to knock is by retarding the timing. That reduces power. If the car would detonate, ping, with the lower octane then using higher octane will allow the timing to be more advanced and the power will be higher with the higher octane. Usually hotter weather makes my cars have more tendency to ping. I've never heard it on the bimmer, however, and I use 89 octane most of the time. But if I am running an autocross I use 93.

I don't really know if 99 would allow more ignition timing but I doubt it. Maybe in really hot weather. I think 93 is plenty for the n55. But I don't know for sure. One way to get some information would be to hook up Torque (via a Bluetooth converter in your OBD II port) and watch your ignition timing. You may find 89 doesn't cost you. I've never bothered to check.

[flinchy]

Originally Posted by Kizzu

And what does that mean in simplified words ?

the engine has a maximum timing value in the tune, think of it as 100%. 93AKI fuel (98RON) lets the ECU hit that value.

without a custom tune, it cannot go over 100%, so putting in higher octane shouldn't do anything at all.

if you live in a hot climate that makes 98/93 not enough octane, it would help, but that's all.

[Kizzu]

Originally Posted by flinchy

the engine has a maximum timing value in the tune, think of it as 100%. 93AKI fuel (98RON) lets the ECU hit that value.

without a custom tune, it cannot go over 100%, so putting in higher octane shouldn't do anything at all.

if you live in a hot climate that makes 98/93 not enough octane, it would help, but that's all.

Basically the tuner told me that the tune gives 250-260 bhp with 93/95 octane and 260-270 with 99 octane. Now the problem is I'm running on 85/87 octane (that's the only fuel available here) and it's giving me 255bhp at the wheels on a 28C day and I want to know if by buying a different type of fuel like sunoco will effect its performance.

[Dackelone]

Originally Posted by Kizzu

Basically the tuner told me that the tune gives 250-260 bhp with 93/95 octane and 260-270 with 99 octane. Now the problem is I'm running on 85/87 octane (that's the only fuel available here) and it's giving me 255bhp at the wheels on a 28C day and I want to know if by buying a different type of fuel like sunoco will effect its performance.

Sounds like your tuner is talking about MON(Europe) octane and not RON(USA/North America) rated octane.

In Europe SuperPlus(ie premium in the states) fuel is rated at 98 octane. Super(or the mid grade - found everywhere) is rated at 95 octane.

And sometimes you can even find Shell V-Power 100 octane or Aral/BP Ultimate 102 octane fuels in European countries.


So... IF you use a good premium fuel in the states you should be producing around 260 to 270 Hp.


FYI... I have a German tune on my 135i. I run 1bar of boost ~14.5 psi. 380 PS and 520 Nm of tq. I always use Esso 98 octane SuperPlus (bc its tax free for me). Sometimes I buy Aral's 102 Ultimate... when I do... I notice that the engine runs quieter and "feels" smoother when pulling hard in gear. I don't feel any more Hp... but the way the engine develops torque does feel different to me. That's just using one tank.

Dackel

[Kizzu]

Originally Posted by Dackelone

Sounds like your tuner is talking about MON(Europe) octane and not RON(USA/North America) rated octane.

In Europe SuperPlus(ie premium in the states) fuel is rated at 98 octane. Super(or the mid grade - found everywhere) is rated at 95 octane.

And sometimes you can even find Shell V-Power 100 octane or Aral/BP Ultimate 102 octane fuels in European countries.


So... IF you use a good premium fuel in the states you should be producing around 260 to 270 Hp.


FYI... I have a German tune on my 135i. I run 1bar of boost ~14.5 psi. 380 PS and 520 Nm of tq. I always use Esso 98 octane SuperPlus (bc its tax free for me). Sometimes I buy Aral's 102 Ultimate... when I do... I notice that the engine runs quieter and "feels" smoother when pulling hard in gear. I don't feel any more Hp... but the way the engine develops torque does feel different to me. That's just using one tank.

Dackel

Thanks for the info ! And yes I am from the EU and the tune is from a british company and that mainly was my concern, as local tuners which are friends of mine told me to be carefull as the uk type of fuel is different from our shitty fuel

[flinchy]

Originally Posted by Dackelone

Sounds like your tuner is talking about MON(Europe) octane and not RON(USA/North America) rated octane.

In Europe SuperPlus(ie premium in the states) fuel is rated at 98 octane. Super(or the mid grade - found everywhere) is rated at 95 octane.

And sometimes you can even find Shell V-Power 100 octane or Aral/BP Ultimate 102 octane fuels in European countries.


So... IF you use a good premium fuel in the states you should be producing around 260 to 270 Hp.


FYI... I have a German tune on my 135i. I run 1bar of boost ~14.5 psi. 380 PS and 520 Nm of tq. I always use Esso 98 octane SuperPlus (bc its tax free for me). Sometimes I buy Aral's 102 Ultimate... when I do... I notice that the engine runs quieter and "feels" smoother when pulling hard in gear. I don't feel any more Hp... but the way the engine develops torque does feel different to me. That's just using one tank.

Dackel

Usa is AKI, not RON, (AKI is RON+MON/2), europe is like australia i think, RON.. If 98 and 95 are normal, same as here.

[Dackelone]

Originally Posted by flinchy

Usa is AKI, not RON, (AKI is RON+MON/2), europe is like australia i think, RON.. If 98 and 95 are normal, same as here.

Yes, same as you Aussies. But NOT the same fuel octane rating as used in the USA.

[TheSt|G]

Countdown to someone wanting Euro gas for the "higher" octane.

[Solo_M_Tech]

And your not making 260-270 hp at the wheels no matter the fuel. That's flywheel power, if your lucky. 2nd, the factory tune is set for 98 octane (euro) and 93 (US) at the maximum timing setting. It cannot adjust for better octane, but it will adjust for lower octane fuel. Unless you get a custom dyno tune for 100 octane+ fuel you will see no difference in power between 93-99 octane fuel. 3rd Dack our cars are boosted, the better octane smooths out the torque delivery because it burns slower. I've noticed it too! :-)

[Kizzu]

Originally Posted by Sinister_1

And your not making 260-270 hp at the wheels no matter the fuel. That's flywheel power, if your lucky. 2nd, the factory tune is set for 98 octane (euro) and 93 (US) at the maximum timing setting. It cannot adjust for better octane, but it will adjust for lower octane fuel. Unless you get a custom dyno tune for 100 octane+ fuel you will see no difference in power between 93-99 octane fuel. 3rd Dack our cars are boosted, the better octane smooths out the torque delivery because it burns slower. I've noticed it too! :-)

1st thise figures are wheel power
2nd my car is not boosted. I have a 125i

[Solo_M_Tech]

Originally Posted by Kizzu

1st thise figures are wheel power
2nd my car is not boosted. I have a 125i

No shit your cars not boosted. That was directed @Dackelone.
2nd, the Stig just dynoed his car with FBO and Evolve tune and only made 235 WHP. Don't get it twisted. He is the expert, IMO, on all things N52/51.

3rd DYNO GRAPH to back up your claimed power. NO stock 125i will make 255 wheel HP. 215, yes. That's been shown.

Unless your FBO (Headers, Intake box of some kind, Cat delete, and Tune etc) you're not making those power numbers.

I'm not hating on you, but it's getting old seeing people mistake flywheel power for actual wheel power.

I came from a 2013 128i with the disa manifold swap with AA tune, Exhaust and Euro intake swap. SO I know WTF I'm talking about. :-)

[TheSt|G]

Originally Posted by Sinister_1

No shit your cars not boosted. That was directed @Dackelone.
2nd, the Stig just dynoed his car with FBO and Evolve tune and only made 235 WHP. Don't get it twisted. He is the expert, IMO, on all things N52/51.

3rd DYNO GRAPH to back up your claimed power. NO stock 125i will make 255 wheel HP. 215, yes. That's been shown.

Unless your FBO (Headers, Intake box of some kind, Cat delete, and Tune etc) you're not making those power numbers.

I'm not hating on you, but it's getting old seeing people mistake flywheel power for actual wheel power.

I came from a 2013 128i with the disa manifold swap with AA tune, Exhaust and Euro intake swap. SO I know WTF I'm talking about. :-)

For the record, I did pull timing.

That said, I don't see 260-270 at the wheels with a bolt-ons motor happening any time soon. Or in this case, the claim of 260-270 at the wheels with just a tune.