Which Petrol?

[hodroyd]

If you get such as 3% & 5.2% difference, how can that not make an overall difference to mpg, if the fuel used was all the same price..?? Or are you saying with various fuel prices the overall cost worked out the same, roughly..??

 

[Contigo]

Ok so 5% on a modern car is not bad if you want the best out of it. Each to their own really!

 

[drewf]

Yep - I suspect that there's no significant benefit to be gained from using higher octane fuels unless the car is being driven hard under load for extended periods, and assuming the ECU is capable of adjusting the engine parameters to make best use of that fuel. Since most of us don't do that on the road, then there's little real difference in day to day driving. On a track, I'm prepared to believe it's different, as it is then possibly running more efficiently for long enough for it to matter.

 

[drewf]

If you get such as 3% & 5.2% difference, how can that not make an overall difference to mpg, if the fuel used was all the same price..?? Or are you saying with various fuel prices the overall cost worked out the same, roughly..??

Exactly mate. The actual cost per mile was approximately the same, given that the SP98 costs more than SP95.

 

[safrane]

I use standard fuel most of the time as the roads and conditions mean you dont have a chance to use the whole performance range. Now if Im on a Euro road trip its the higher octane as the car is driven more vigorously.

 

[Contigo]

When the new 997 GT2 came out Porsche said that running it on 102RON BP fuel and having the ECU tweaked would result in 100bhp gains..

 

[hodroyd]

Sounds a good idea then..!!

 

[hawkeye651]

For what it's worth just back from a fab visit to DMS & Rob said that the Bosch ECU could detect 97 v 95 RON 'after a full sweep through the rev range'. Once 'happy' it would default to the 97 power curve - apologies if any of the above got lost in translation!

 

[hodroyd]

So 97 will give better performance..!!

 

[CatmanV2]

Erm, not unless you know what the difference is between the power curves.....

C

 

[hodroyd]

My ECU and DMS software should though..!!

 

[CatmanV2]

My ECU and DMS software should though..!!

Oh yes!

C

 

[TridentTested]

'after a full sweep through the rev range'. !

At last, a rational reason to red-line it: 'Honestly officer, I was only getting the ECU to recalibrate the RON after my last fill-up'.

 

[CC4200]

I do my best to redline once a day even if only in first, although second does sound better

 

[Chrisbassett]

Redline in first is too harsh, second is much more fun! Third is a luxury and 4th is getting scary on most roads!

 

[CC4200]

I'm too pretty to go to prison Chris