Shell V Power fuel...

Emp_Fab

Has anyone else tried it ?  I've filled up with it a couple of times before and noticed a definite performance boost, but it was only today, about 30 miles after filling up on the V Power Diesel that I noticed the dash estimating over 800 miles worth left in the tank.  Normally that never goes above 590 when I fill up.  It's based on the average mpg since you filled up last.  

Thinking this was a glitch, I switched the display to show the current MPG and was gobsmacked to see that the car was managing 98mpg on the flat with the cruise control at 50mph.  NINETY EIGHT MPG !  Once I got up to 70, it had dropped to 50-odd mpg.  That's insane !!

I'm keeping track of the actual mileage I do until the next refuel, just in case the computer has lost its marbles or the fuel-flow sensor has had a fit, but so far I have no reason to disbelieve it.  If it turns out to be correct, the extra cost of the V Power fuel will be hugely outweighed by the insane mpg I'm getting from it.

Deijavoo

I definitely get more mileage with whichever brand of premium. No idea exactly but I should check really.

ICBM

It's also possibly because you're driving like a sensible person these days .

Just look at the efficiency difference between 50mph and 70... you're burning nearly twice as much fuel just to go 20mph faster. If you don't want to do 50, try it at 60 - you'll probably find it's much closer to the 98mpg than the 50-odd.

It's not just high speed by itself that wastes fuel, it's constantly speeding up and slowing down, which is inevitable if you're trying to go too fast unless the road is totally empty. If you stick rigidly to a fixed speed your economy will improve. So ideally you need to find the speed which allows you to do that relative to the other traffic - I do tend to find it's just below 60, because that's very slightly faster than most of the lorries so it allows time to plan overtaking. Just by doing that I get almost 50% better fuel economy than I did when I drove more "normally" at around 70.

It's an interesting thought to realise how much we could reduce the consumption of oil if everyone did that... as well as the money it saves you.

Jalapeno

I try to use it, some Shell garages don't have it, but it is flipping expensive .... It does make a difference to mpg - I think it is marginal financially, meaning the extra cost = the improved mileage savings.

chillidoggy

That was 98 MPH, not MPG!

Fuzzdog

I've generally found that premium diesel does give better mpg and a dash more torque in most cars.  Of course, the higher price means it probably balances out in terms of overall cost, but it does keep your pumps nicely lubed (ooer missus), injectors clean, etc.

Varies a lot with premium petrol - most cars see no change at all, but if a car can adapt to it you can see some nice benefits.  

It always amuses me when I see someone with a fancy high powered car putting regular petrol in the tank to save a few pennies - if it's designed for higher octane fuel from the outset, it's probably retarding the ignition like crazy on cheaper fuel, doing terrible MPG, and would be much cheaper to run if they just put the right fuel in in the first place.  My old Saab 9-5 Aero would struggle to hit 30mpg on a long run on regular petrol, stick a tank of premium in and it would do 45mpg on the same trip even if you booted it a few times to overtake/have fun/IswearIwasonlydoing70occifer, which more than made up for the higher price per litre.

Jalapeno

Fuzzdog said:

It always amuses me when I see someone with a fancy high powered car putting regular petrol in the tank to save a few pennies - if it's designed for higher octane fuel from the outset, it's probably retarding the ignition like crazy on cheaper fuel, doing terrible MPG, and would be much cheaper to run if they just put the right fuel in in the first place. 

My buddy used to have a super-charged Jag XF - when replacing his third catalytic convertor the mechanic asked him if he was using supermarket petrol - he was

Axe_meister

The most efficient speed to travel at is 56mph.

Due to things like boundary layer separation(reduced drag), optimum revs/gearing.

ICBM

Even in my cheapo Renault, supermarket petrol is poor value for money - the slightly worse fuel economy just outweighs the cost saving. The additives in even normal unleaded petrol are important.

Most people don't think to check this, they just look at the pence per litre and think they're saving money, when they're actually burning more fuel and possibly shortening the life of the engine.

mike_l

I refuse to use supermarket petrol, have done for years.

I had an Astra SRi many years ago, and if I put supermarket (IE Tesco) petrol in, it ran like a sack of spanners. Yet if I put Shell (or BP Etc) in even the lower grade stuff, it ran fine. Ran brilliantly if I put in Super unleaded.

Also a couple of years ago, we (at work) had a spate of cars needing new Lambda (oxygen) sensors as supermarket fuel had contaminants (IIRC rubber particles) which were blocking them up.

And the winter before last the diesel from various supermarkets was (crystalising) freezing at well above the point it should have been (crystalising)freezing at, and blocking diesel filters.

Cirrus

Axe_meister said:

The most efficient speed to travel at is 56mph.

Due to things like boundary layer separation(reduced drag), optimum revs/gearing.

I've found on rare occasions where I could go slower on the flat for a prolonged period, for example an A road trundling along behind a lorry, the efficiency keeps going up the slower you go in top gear down to the point where the engine's starting to struggle. The problem then is that if you need to accelerate or go up a hill the engine's not in its most efficient range so that's when you lose out.

On the straight and level it's amazing how efficient cars can be. It really is the accelerating that rapes the fuel economy - both hard acceleration and unnecessary acceleration and of course the associated breaking that goes with it which is effectively using fuel to heat your breaks. I've found saving fuel to be a battle on two fronts; Firstly to accelerate as gently as you can, and plan ahead so you're not speeding up pointlessly just to slam on the breaks a hundred meters down the road. Obviously the balancing act then becomes how slowly you can accelerate without infuriating everyone around you or causing danger! Secondly to cruise as slowly as you deem safe and not annoying for those around you. Typically on motorways I'll do 70 but be on the lookout for a lorry with a speed that's not oscillating wildly that I can just tuck in behind.

Of course, all that is contingent on not being bored/ late/ excited to get somewhere. And I'm an excitable chap.

ROOG

I have been running an experiment since this time a year ago, Shell normal unleaded vs V-power super unleaded. I switch roughly once every couple of months so I get a good flush out of the previous mixture each time. Apart from the extra cost I don't notice any difference in fuel consumption. If any thing the change of seasons probably affects the mpg more. My car isn't a performance model and doesn't require the higher octane rating.

I will continue to use branded fuel in my car but one thing I am starting to look for is fuel that includes less ethanol, I gather that it isn't good for petrol engines and that it is the green/sustainable lobby that force its use in Petrol.

I understand that some higher octane types have less ethanol in it.  This could be reason alone to pay for the premium product.

monquixote

With diesel I have noticed a slight improvement to MPG if you use fuel additives like Millers, but I've never taken the time to work out if it is an actual saving or not. It did used to have the effect of making the engine light go off when it used to occasionally come on in my old car. Presumably because the cleaning agents removed all the clagged up stuff. 

The main thing I've noticed is the considerably lower economy in winter and when using the air con. 

My best tip for improving economy if leaving a big braking distance on the motorway so you don't have to use your brakes all the time.

lustycourtier

mike_l said:

I refuse to use supermarket petrol, have done for years.

I had an Astra SRi many years ago, and if I put supermarket (IE Tesco) petrol in, it ran like a sack of spanners. Yet if I put Shell (or BP Etc) in even the lower grade stuff, it ran fine. Ran brilliantly if I put in Super unleaded.

Also a couple of years ago, we (at work) had a spate of cars needing new Lambda (oxygen) sensors as supermarket fuel had contaminants (IIRC rubber particles) which were blocking them up.

And the winter before last the diesel from various supermarkets was (crystalising) freezing at well above the point it should have been (crystalising)freezing at, and blocking diesel filters.

I know a number of Taxi drivers who refuse to use Morrisons fuel. Its the worst of the worst by all accounts.

mike_l

^^All those (Except the Astra) were from Tesco, Morrisons, and Sainsbury's

Axe_meister

ROOG said:

I have been running an experiment since this time a year ago, Shell normal unleaded vs V-power super unleaded. I switch roughly once every couple of months so I get a good flush out of the previous mixture each time. Apart from the extra cost I don't notice any difference in fuel consumption. If any thing the change of seasons probably affects the mpg more. My car isn't a performance model and doesn't require the higher octane rating.

I will continue to use branded fuel in my car but one thing I am starting to look for is fuel that includes less ethanol, I gather that it isn't good for petrol engines and that it is the green/sustainable lobby that force its use in Petrol.

I understand that some higher octane types have less ethanol in it.  This could be reason alone to pay for the premium product.

On a non turbo/super charged car there will be no difference between low and high octane fuel as your ECU may adjust itself to prevent pinking. You could even end up using more fuel.

gubble

I've not used Super Unleaded in my cars however always use it in Motorbikes. Better fuel economy and increased power. The extra  MPG certainly outweighed the extra cost at the pump.

However these were all with carb based fuel systems not injection based.

Fuzzdog

monquixote said:

My best tip for improving economy if leaving a big braking distance on the motorway so you don't have to use your brakes all the time.

Would be lovely were it not for the fact that every time I do that, some other twit (occasionally two!) decides that he'll pop into that space, cutting my braking distance in half.  One of my pet peeves of motorway driving, that one, as I've had a couple of near misses over they years and like to keep as much space around me as possible these days.

Watched a shiny new Mercedes go past in the inside lane the other day following a van, apparently these new super Mercs have such good brakes that he thought that about six feet was suitable braking distance at about 80mph.  The van got out of his way, and he proceeded to follow the next car at the same distance.  Scary. @-)

Sambostar

There is no way in hell I am putting V Power diesel in my 2.5Di Ford Transit.

chillidoggy

Tightwad.

Thing is, it'd be like driving a Ferrari, hot chicks will swoon when you pull up at the kerbside in your Shell V-Powered Tranny tipper, lean out of the window, and ask how much it costs for a shag.

FX_Munkee

Unless you have a seriously clever ecu that can remap itself on the fly to suit different octane rated fuel. You are simply seeing the effects of the added detergents in the fuel, cleaning your injectors. Unless, like @gubble you're using carbs, then you will see a small improvement.
The only caveat to this is what @Axe_meister said about pinking, but if your engine is pinking on normal fuel then you've got far more to worry about.