Unleaded or Supreme/Premium?

[adann]

Interested to know what people use in the way of petrol on a 23i? Do you go for standard unleaded or the supreme/premium stuff?

Anyone notice a difference in performance/mpg with the premium?

[flybobbie]

I was wedded to Sainsburys premium, and occasionally Shell nitro+.
I did notice a difference using Sainsburys unleaded, but now use Shell unleaded as it feels as good as Sainsburys premium.
I think the mpg went down as it seems to rev better, so I like to put my foot down.
I think the cleaning properties of Nitro made a difference.
It certainly bunged up the carbs on the motorbike the first time I used Nitro!

[DanHZ4]

I always use super in my 23i it definitely picks up better. My main reason for doing so is fuels with a higher RON are better for the engine and injectors. I'm not sure it actually makes much difference mpg terms, driving style is a bigger factor.

Personally I only use branded fuel the likes of Texaco, Bp and Shell as I noticed supermarket fuel didn't go as far but that could be just me!

[Northotheborder]

I always use super unleaded, a very good mechanic told me that unleaded fuel was a false economy and to avoid buying cheaper fuel from supermarkets.

[KERMIT1970]

I use super unleaded as I found I was getting a extra 40/50 miles a tank more than regular unleaded. Can't say I notice any better performance.

[goldbcfc]

I've used super/premium for last 10yrs in all my bmw's it cost like £3 per tank more than regular fuel you get better mpg and it protects your engine and fuel system to highest quality. So its a no brainer really


Question: do you use regular or premium oil ?

Answer: if you do use good oil then you probably use good fuel too as the benefits out weigh not using it. If you don't use premium oil then stick to regular fuel as your obviously not bothered about the cars maintainence so why start......lol

[Scooba_Steve]

I was wedded to Sainsburys premium, and occasionally Shell nitro+.
I did notice a difference using Sainsburys unleaded, but now use Shell unleaded as it feels as good as Sainsburys premium.
I think the mpg went down as it seems to rev better, so I like to put my foot down.
I think the cleaning properties of Nitro made a difference.
It certainly bunged up the carbs on the motorbike the first time I used Nitro!

Sainsbury's super is only 97. Tesco/esso is 99 for usually the same price. I believe shell v power is also 99 but I find it significantly more expensive. If I ever have to fuel at Sainsbury's I just use the cheap stuff. Only had to do it once or twice.

[dk345]

I have a 35iS rather than a 23i like the OP, but I aim to always use VPower or BP ultimate depending on where i fill up.

The previous owner told me that's all he ever put in it, so I thought I'd carry that on. The one time I used standard BP unleaded was when my work station was out of ultimate. I honestly couldn't hear or feel a difference, but I did get 35miles less than I normally do before needing to fill up again.

I suppose that for a "high performance, tuned" engine like the one in the 35i or 35iS the higher RON may make a difference with regard to engine longevity or perfomamce, but from what I've read that's rather disputed anyhow.

Like a previous poster said, it's only a few quid more per tank and the extra things in the more premium fuels can't make it any worse...

[adann]

Thanks for the replies. Will start filling up with the premium stuff.

Didn't want to go ahead and do it and realise after it was a bad move.

[Garvin]

The higher RON will provide increased performance in modern engines with knock sensors and adaptive ECUs, particularly noticeable with turbo charged engines. The higher RON has nothing to do with engine/injector longevity etc., that is do to the enhanced detergents/cleaners the various oil companies claim to include in their higher RON offerings.

Indeed, it is the additives which are the only difference twixt the major oil companies fuel and the supermarket supplied stuff.

In theory then, the higher RON fuel should provide more mpg in absolute like for like comparisons, but if you make more use of the improved performance then it is highly unlikely you will see any material gains in lower fuel consumption.

[Ducklakeview]

I only ever use premium unleaded & diesel in my cars/van. I fill up at Costco, indeed I did so in the van this morning, and prem unleaded and diesel is 105.9p plus I get 2% cashback on my exec reward, and also another 1% on the Amex, so work out around 102p/L.

Mike

[ronk]

It will be best if you do search on this subject on the forum - there is every answer you will ever need!