[barrie74]

Sorry if there already is a thread but couldn't find one. Does anybody know whether the Engine management system on the Mini is capable of automatically adapting to fuels with higher octane contents. I was talking to shell expert and he was saying that the reason some people report no benefit from using optimax is because the engine timing on there car is set to use 95RON so the piston compression could not make use of a higher RON so the improvements would be negligable.

Will my mini cooper make the necessary adjustment for me if I start using Optimax.

Also has anyone tried using any fuel injector cleaners in their tank and have they noticed any performance or mpg improvements

[SoggyCornFlakes]

I've found Optimax or Ultimate does give my Cooper some extra zip

[HarryHBMCC]

Please see http://www.mini2.com/forum/showthrea...ght=adaptation.

Harry

[barrie74]

Quote: Originally Posted by HarryIndiBlue

Please see http://www.mini2.com/forum/showthrea...ght=adaptation.

Harry

Thanks but I'm not sure still whether the ECU actually adapts the engine/piston timing to compensate for higher octane fuel. I would guess yes but wondering if any techs could give me a definative yeah or neah

[HarryHBMCC]

Please read the thread. A tech. named Andy answered and mentioned how the fuel/air mixture, etc. readings lead to adaptive compensation.

Harry

[barrie74]

Quote: Originally Posted by HarryIndiBlue

Please read the thread. A tech. named Andy answered and mentioned how the fuel/air mixture, etc. readings lead to adaptive compensation.

Harry

Thanks again but I was after a specific answer and having got a degree in Engineering I am sure that most cars do what Andy is sugesting is matter of science of combustion, however what I wanted to know was whether the the software could specifically change the engine valve timing because it was intelligent to understand what fuel was being used. What Andy is explaining in the thread you pointed to is more about how the car adapts to how it's being driven.

Am I led to believe that you help to moderate the site, the problem is that with so many threads it takes too long to find the answer and if we had that much time to kill we'd ring BMW customer services, also most threads seem to go off at a tangent after about 5 or 6 replies because people ask another unrelated question so it's hard to keep track. However many thanks for your help as the thread you pointed out to me might just explain the poor fuel consumption on the car.

[agiduda]

Quote: Originally Posted by barrie74

however what I wanted to know was whether the the software could specifically change the engine valve timing

Please apply basic engineering research skills and read the FAQ concerning the engine itself - it has no variable valve timing to adjust.

In case you are too busy "engineering" here is a direct link to engine details:
http://www.mini2.com/pdf/mcs_powertrain_us.pdf

[HarryHBMCC]

Barrie, that was the best thread I could find. Sorry it didn't answer all your questions. Perhaps you could PM Andy to see if he knows something specific to your query.

This thread, http://www.mini2.com/forum/showthrea...ght=ecu+octane, contains some conjecture about ECUs adapting for octane but it is just that. Empirically and anecdotally, many people have noted that the anti-knock seems to remember for a while when you put poor fuel in and it takes a while to let the timing move back to optimum when high octane fuel is used again but I haven't seen any firm documentation of this feature.

Harry