Super Unleaded + M54 engine - Give it a chance!

[Rudd]

just for an update. halfway through my second tank now and the MPG is creeping up. on my daily driving that is usually 29mpg at this time of year im getting 31.7mpg. i am aware that subconciously im driving a little more carefully but i can feel the difference in the throttle and the engine idle is smoother.

i can feel the pennies making my pocket heavier now

 

[daveg]

Going to join in and give some V Power a try now

 

[adjenkins]

All i can say is that unless you reset the ECU, the car seems to take around 500-750miles of mixed driving to fully adjust the fuel tables to advance ignition timing of higher octane fuel. After this time, the difference is marked, especially in med/high throttle 'closed loop' (ECU feedback loop using lambdas) operation! After 3 tanks on the same regular 45mile journey i was averaging +1.5mpg (fill to fill, NOT computer) and the car literally felt as though it had ~15% more power at low rpm, high throttle situations. Throttle resonse was somewhat improved and the engine sounded a *lot* smoother under high load with the sound generator foam removed.
Thanks for reading

What is the best way to reset the ECU?
On a previous car I used to disconnect the battery every so often as I drive like a girl and the engine management system seemed to adapt to this 8)
Reason I ask, the car an M is getting a remap at the weekend. Should I reset the ECU to ensure that any further imrprovement is noticeable. Also wondering should I fill up with 97 (best we have in NI I think) before the car goes on the dyno for the remap.

cheers

 

[Muzz]

Going to give this a try, just means I'll have to use that 1/4 tank left on the way home from work

 

[Sticks]

All i can say is that unless you reset the ECU, the car seems to take around 500-750miles of mixed driving to fully adjust the fuel tables to advance ignition timing of higher octane fuel. After this time, the difference is marked, especially in med/high throttle 'closed loop' (ECU feedback loop using lambdas) operation! After 3 tanks on the same regular 45mile journey i was averaging +1.5mpg (fill to fill, NOT computer) and the car literally felt as though it had ~15% more power at low rpm, high throttle situations. Throttle resonse was somewhat improved and the engine sounded a *lot* smoother under high load with the sound generator foam removed.
Thanks for reading

What is the best way to reset the ECU?
On a previous car I used to disconnect the battery every so often as I drive like a girl and the engine management system seemed to adapt to this 8)
Reason I ask, the car an M is getting a remap at the weekend. Should I reset the ECU to ensure that any further imrprovement is noticeable. Also wondering should I fill up with 97 (best we have in NI I think) before the car goes on the dyno for the remap.

cheers

I know if you switch the ignition on, press the accelerator to the floor, then switch the ignition off it resets the way the auto box adapts to your driving style to default settings. Just that or does it do the ECU? Not very tech I'm afraid so don't know.

 

[PCBung]

Well I did a fill up of Tesco 99 last night (full tank), and I can say the engine is quieter... I was going to take the car the the garage to ask em why it seems abit "ticky" but now alot of it has now gone.

Sadly the nearest Shell garge is around 5 miles out which is on the way to my old gym whichs means I will have to sign up again to make use of it lol!

Has anyone tried Jet's Super unleaded? I like how they hide the price and as you put it in it dings up 116p when 95 ron was 105p lol

 

[Siftah]

Yes its true, but the difference is tiny...

The colder the fuel, the higher the density, due to the molecules vibrating less. The relationship is called the coefficient of thermal expansion (with a greek BETA symbol).

From memory as i brushed up al little on this whilst doing my PPL, the weight difference of 1 litre of fuel differs around 10ml per litre between 0C and 10C

Add to this that fuel is stored in huge underground tanks - the temperature below ground doesn't vary anywhere near as much as above ground. I would suspect, therefore, that the difference in temperature during the day/night varies by only a couple of degrees at most.

I wouldn't think it's worth getting up early for

Though, I don't think there's much in life worth getting up early for...

 

[SLK Driver]

I have a tesco clubcard and a Clubcard Credit Card, so I get points wherever I shop with the CC!! I use it for my business expense I put about 25k a year on it, result! If you spend the points value in store you're daft. So when I pick up the Z4 I'll just use the 99RON stuff, no point in doing it on the SLK.

I've got a gold rally day booked from Everyman Racing in liecester, totally FOC! We get about £200 of vouchers (or £800 of trade ups) every quarter.

http://www.ferraridriving.com/tesco_rally_gold_experience_25.htm

 

[Siftah]

So, I'm thinking I'll give Tesco 99 a try.

I have the Rev software which can log OBD readings from the engine management and I'm planning on logging some values to see how the engine responds differently - ie: how long does it take to reset itself.

Which PIDs do people think would be worth logging? I'm thinking timing advance for certain. I think I'll need engine temperature and engine load with this for the data to be any use?

I can log five, so:
- Fuel Trim LB1
- Fuel Trim LB2
- Timing Advance
- Throttle
- MAF Rate

I think the long term fuel-trim only gets updated once the engine gets warm, this is where I'm expecting to see the value slowly change over time as the engine gets used to the higher octane fuel. Comments or suggestions?

 

[daveg]

No suggestions from me but that sounds very interesting and I look forward to hearing your results.