Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Wayne]

Guys - not sure if this has come up before
but on my 10 year old V6 Estate, is there any benefits on putting the slightly more expensive petrol in than the usual stuff? reading so many different opinions all over the net, thought id ask "the men in the know"
was gonna fill her up tonight, wondered if its worth doing a test on a full tank, or have you guys noted anything?
i drive 28 miles a day in total now with me crappy night job, i leave her on cruise control at 60 mph there and back, as im no hurry, or im just tight! 

[Jimbob]

the best benefit is the cleaning additives for cars of our age, your not going to get much / any noticable performance / economy benefits.

You will likely find the car runs smoother both on that, and the next few tankfuls of ordinary too 

[pembsomega]

on an omega youll get zero performance gains putting any knid 'expensive' fuel in. 

the octane rating of a fuel is an indication of its resistance to knock or produce detonation (underfueling and melting pistons)

as our engines are tuned to run on our standard 95ron unleaded then there is nothing to gain from constantly filling up with anything other than normal unleaded.

fuels like bp ultimate etc do claim to have added cleaning additves but again their usefulness are questionable

[Kevin Wood]

Yep, what he said.   

With 95 RON at £1.20+ a litre who needs an excuse to hand over more?

Kevin

[jereboam]

I started a similar thread six months ago.  I know that the others are right - technically there should be no noticeable difference when you use premium petrol.  For that reason, I always used to fill up at wherever was cheapest - usually Morrisons or Asda.

However, I experimented with Shell V-Power, and I now really do think it's better.  I do a lot of 5 to 10 mile journeys, and I get significantly better fuel consumption on the premium petrol.  My 3.0 V6 will return about 34 mpg on a trip from Suffolk to the North London suburbs, which is better than the 28 I used to get.   I even managed Ipswich to Bristol and back on one tankful.

I don't think it is actually saving me any money, though, because the extra MPG is cancelled out by the 7p a litre extra on the price.   

[jonathanh]

well to add to the debate......

I used to use supermarket fuel a lot and always had a slight misfire from cold when leaving my village.  always ignored it because it was quite rare and I  thought I'll let it get worse before tracking it down.

then my local shell station started matching tesco prices so I switched to them, and addly enough the misfire has gone away.  All of this could be my imagination but as my local shell is no more expensive I tend to stick to that.

as for the higher octane, I would imagine that you get slightly better MPG as a little offset to the cost but I don't think it is worth it so I stick to the expensive stuff rather than the very expensive stuff.

[Jimbob]

Supermarket -v- Branded is a very different debate, and Branded every time for me 

[pembsomega]

Supermarket v branded is a none debate, makes no difference as supermarkets get their petrol from the big oil companies, I've worked on both texaco and murco refineries in Milford haven, and as many supermarket branded tankers leave those sites as company branded ones. Tescos petrol here is the same as murco as morissons is texaco. There is no difference.

Octanerating make no difference to mpg, as I said an omega engine has no ability to make any advantage of a higher octane rating and anyone who thinks they know a difference is just kidding themselves

[miniator]

for the sake of an extra £2-4 a tank i always used super (only 97 in NI though) in my omega.

More power, smoother, more miles to a tank and would pop and bang a little when slowing down through the gears which always made me smile!

I worked out i got 4-5mpg more on super than normal. average of 23 on normal, average of 27 on super.

run normal as you are for a few fill ups and then switch to super (first tank will be neglilable differnce until the ECU adapts) and then compare them

[miniator]

Supermarket v branded is a none debate, makes no difference as supermarkets get their petrol from the big oil companies, I've worked on both texaco and murco refineries in Milford haven, and as many supermarket branded tankers leave those sites as company branded ones. Tescos petrol here is the same as murco as morissons is texaco. There is no difference.

Octanerating make no difference to mpg, as I said an omega engine has no ability to make any advantage of a higher octane rating and anyone who thinks they know a difference is just kidding themselves

wrong

[bob.dent]

Autoexpress magazine ran a main feature testing all branded and supermarket fuels a couple of months ago. The extensive tests they ran included chemical analysis as well as performance and mpg. The results showed that there was very little difference between them but a couple of the supermarket fuels actually scored slightly higher than branded. I always use Sainsbury's fuel and have never had any problem with it.

[Jimbob]

Well I know mine doesnt run well on a variety of supermarket fuels, can feel differences in how it runs on various branded ones too...

live data even shows knock retardation sometimes occuring when its been on Tesco's fuel, never does that with shell.

[coastie123]

Autoexpress magazine ran a main feature testing all branded and supermarket fuels a couple of months ago. The extensive tests they ran included chemical analysis as well as performance and mpg. The results showed that there was very little difference between them but a couple of the supermarket fuels actually scored slightly higher than
branded. I always use Sainsbury's fuel and have never had
any problem with it.

unfortunately I have to travel 12 miles to get saubsbury fuel which i have never had a problem with either..

I tend to use either shell or jet for fuel depending which is cheaper.. At the moment fuel is...
 
shell 118.9
tesco 120.9
bp 123.9
jet 121.9

so as you can see it varies quite alot.. The only petrol station where I live is jet so I always fill up when I'm at work in exmouth which is about 25 minutes drive... On tfe other hand if I happen to be in Exeter I use sainsburys which tends to be 2p cheaper than shell exmouth... So the only unbranded fuel I use is sainsburys when I can get there but most of time I use shell.... 

[pembsomega]

Miniator I'm sorry but a fuels octane rating purely shows it's resistance to knock or detenation as it's also called. As omegas are set up to accept 95 ron fuel putting fuel in of a higher octane will give no performance gains unless the car is remapped to take advantage of the higher octane rating. Which would the result in poor running if you ever put a lower rated fuel in.



Remapping a normally asperated for a higher octane fuel is a waste of time, you'd spend hundreds for would would only be  a few horses gained. Forced induction engines however Beirut hugely from a remap to run on higher octane as with the increased resistance to knock you can run at high boost levels etc........

http://www.google.co.uk/search?hl=en&defl=en&q=define:octane+rating&ei=593GS-CeIJHw0wTD3IjUDA&sa=X&oi=glossary_definition&ct=title&ved=0CAYQkAE

as omegas are set up to run on 95 ron running a higher rated fuel wont help, yes it will be less likely to knock but t wont increase any performance

as fuel has to reach a stanard to be given its octane rating you really should see no difference between any fuels rated at 95 ron or 97 ron

differences may be present due to poor storage or age of fuel, but that would vary from site to site not brand to brand.


i had a cavalier once and that had a plug that you could swap round in the eninge bay if you were running on 95 or 97 ron fuel made no differnece thought maybe a few more mpg on 97 but that was totally balanced by the extra cost of super unleaded.

[mathewst]

I tried couple of tanks of OMV premium 100 octane fuel available here.
Car worked better, you couldn't hear it almost when on idle, but the mpg dropped also slightly  :-/
So I think not much point in using high quality fuels.
Tried recently using additives (STP injector cleaner and it seems this stuff  helps) Niow car works like a charm.