Experimenting with supermarket/branded fuels

casper_g

8u87fhsd wrote: »

Octane levels - no ideas.

2.2 Toyota Diesel

Fill up on Asda regular diesel ~ over 6000 miles avg 42mpg
Fill up on Shell regular diesel ~ 23000 miles avg 48mpg

What time of year was that? Could the Asda have been selling stock of winter diesel while the Shell place had summer fuel (as mentioned by Hammyman above)?

Hammyman

newfoundglory wrote: »

Having filled up this morning with Shell regular unleaded I can report that my car does appear to run smoother. Examples include it not being near-stalling when revs are low... such as setting off from lights or reversing into the drive.

Im sure i'm not imaging it. My car has a pretty unrefined engine.

Having also filled up with Shell this morning, I can report that my car appears to run like a dog with some hesistation around the 2500-3000 RPM range.

Hammyman

8u87fhsd wrote: »

Same Car
Same driving style
Same route
Asda avg 42mpg
Shell avg 48mpg

Even though Shell is slightly more expensive per litre I'm still saving money.

Quite possible. Subconsciously you believe it so you alter your driving to achieve it.

System

I refer my honourable friend to post #2

I won't say I told you so.

artha

I'm sure I saw a (scientific?) study somewhere which asked the question are super fuels worth the money. Under controlled conditions I believe the conclusion was that for the average car driver there is no detectable difference in terms of power. For more powerful(sporty?) engines there was a minor detectable benefit in bhp. As to the benefits of cleaning agents I think the study concluded that it was too difficult to determine whether there was any benefit at all. I suppose you'd have to run identical engines under identical conditions for several years and then strip them down and have a look

worried_jim

Bob_the_Saver wrote: »

Convert to LPG, half the price of that petrol stuff & about 52p per litre here in France

Or drive a diesel and run it on waste veg oil for free !;)

Shimrod

I drove my previous car for two months on shell v-power, and for two months on ASDA fuel - that's around 4,000 miles on each type of fuel. The V-power did give slightly better fuel consumption, but only around 0.5mpg, and certainly not enough to justify the premium price. Can't say I noticed any difference in performance either.