Petrol - Standard or Premium

duggiesmith · Post by **duggiesmith** » Tue Jul 03, 2007 10:00 am

Can anyone tell me if they notice any difference between standard unleaded petrol or premium unleaded.

I try to use premium when possible, but can't say I've noticed the difference in performance (although I don't take the car on the track and get very few chances to open it up legally on the roads around Edinburgh

I like to get away up North once or twice a year where the roads are quieter but often find it difficult to get premium unleaded. If it does make a difference, it would be nice to know that I may have that little bit extra when overtaking!

Post by ed » Tue Jul 03, 2007 10:03 am

Depends on the type of your car! Toyota engined cars are the only ones that have knock sensors IIRC! hth cheers Ed

duggiesmith · Post by **duggiesmith** » Tue Jul 03, 2007 10:06 am

07 plate Elise S - Standard spec Toyota engine

Post by **Shug** » Tue Jul 03, 2007 10:06 am

It'll do jack (well, virtually). If it's a new "S" it's the Yota engine so it may have a knock sensor, so might give you a bit more leeway on the ignition timing, but the Bum Dyno would need to be calibrated very well to feel it!

The reason some people with standard engines use V-Power or Ultimate is more to do with the detergents in it. I use it as I've got programmable engine management and it's mapped for 99 octane. It means I'll get a few more HP, but that's really more to do with printout bragging rights than actual performance TBH....

On a standard Yota engine it might give you 2bhp which would do nowt in the grand scheme of things

Dominic · Post by **Dominic** » Tue Jul 03, 2007 10:08 am

The golf is the first car that I have had a noticeable difference.. it's supposed to run on 98RON, and when i use 95, it is slower, and lumpy at idle. It's a turbo, which apparently get the biggest gain from higher octane fuels.

Never noticed that much difference in other cars, but I do remeber someone years ago (FD?) saying that when they dismantled their engine, it was in much better nick, having been run on higher octane stuff.

The healey (1961 technology) runs far better on higher octane than the standard stuff.... apparently helped by the fact that the better fuel does not go off quite so quickly.