Best Petrol in UK? Plus I need a new car... any suggestions? Please...

[rjbetty]

Hi everyone,

I use my car a lot these days for work and find I am doing about 2,000-3,000 miles per month!!! It kinda uses a lot of fuel.

I had been getting fuel from a cheapo station but... I found that the mileage is actually TERRIBLE. So would anyone here have an idea of which fuel is the best value (not necessarily the cheapest).

Also, my Vauxhall Astra, now with more than 138,000 miles on the clock is on it's last legs and it's time to get a new car. Bear in mind that I have NO money so was wondering what would be a good car to have. It has to be second-hand. I've heard that Volkswagens are very good, but I want a Ford Focus; something that runs reliably and importantly has GOOD mpg!!!!!!!

Ah appreciate any comments. Over.

[Brown, Jon Brow]

Budget?

[rjbetty]

Budget?

Literally zero! I'm thinking of getting a decent one like a Focus on finance or something...

UPDATE: Just tried to start my Astra only to find it's literally and completely dead.

[D-Type]

Despite what people say, I don't believe there is that much difference between different brands of fuel. It comes from the same refineries, the independents simply buying excess production from any of the majors. The only possible difference is that some brands may have been blended down to meet the minimum octane number allowed, but if that has been done it won't be below it.
As to car choice I simply don't know. I have had bad experiences with two VWs but my brother in law swears by tham and won't have any other car. If buying secondhand you will often get more car for your money if you get a less popular make like a Hyundai. With the mileage you do, it is worth buying a car with low mileage for the year which you will be able to sell in a year or two as an average mileage car. It's generally cheaper to get a bank loan than buying on finance.

[janneppi]

Is diesel cheaper with mileage around 20-30k miles per year in UK?
Get a Volvo S40 2,0D, you get Ford Focus handling with a reliable(ish) Peugeot engine.

[Mark]

All fuel from UK petrol stations adheres to the same standard and is the same. So it makes zero difference where you buy from.

Last time I checked they don't give cars away so you are going to need some budget. Even for a Focus

[rjbetty]

All fuel from UK petrol stations adheres to the same standard and is the same. So it makes zero difference where you buy from.

Last time I checked they don't give cars away so you are going to need some budget. Even for a Focus

Aw ok, I heard this may be the case. In that case maybe I should just stay away from supermarket fuel as a rule. But I did find an independent petrol station that was cheaper than any other. However it's fuel has TERRIBLE mileage!

As for the car, I was hoping Matt Wilson would give me his 2010 Focus seeing he isn't using it anymore. Failing that, I am relying on the generous people of motorsportforums clubbing together and buying me a new machine. Thanks guys, appreciate it. :P

[tfp]

Despite what people say, I don't believe there is that much difference between different brands of fuel. It comes from the same refineries, the independents simply buying excess production from any of the majors. The only possible difference is that some brands may have been blended down to meet the minimum octane number allowed, but if that has been done it won't be below it.
As to car choice I simply don't know. I have had bad experiences with two VWs but my brother in law swears by tham and won't have any other car. If buying secondhand you will often get more car for your money if you get a less popular make like a Hyundai. With the mileage you do, it is worth buying a car with low mileage for the year which you will be able to sell in a year or two as an average mileage car. It's generally cheaper to get a bank loan than buying on finance.

Depends on the car, I can't imagine many factory standard cars that would change in performance or MPG through using different fuel.

But if you look at reasonably highly tuned cars that's when it does make a difference. Reliability more than anything else.

Lower octane fuel usually has lower burning temps, leading to detonation and melted pistons etc. I'm sure others with more knowledge on this forum can tell more.

[Rollo]

Depends on the car, I can't imagine many factory standard cars that would change in performance or MPG through using different fuel.
But if you look at reasonably highly tuned cars that's when it does make a difference. Reliability more than anything else.

This is a handy link to do with the calorific value of various fuels:
Calorific Values | JATRO

In general, running a higher octane rated petrol in an engine does diddly squat because all petrol, regardless of its octane rating, has pretty much the same amount of energy per litre.

Lower octane fuel usually has lower burning temps, leading to detonation and melted pistons etc. I'm sure others with more knowledge on this forum can tell more.

Lower octane fuel by definition burns faster. The whole point of a higher octane fuel is to make the burn more slow and by extract more energy from increased compression ratios. The thing is that an engine by design is specific for an octane rating. If you choose to put a higher octane rated fuel into your car, that's fine but you don't actually change the physical dimensions of the combustion chamber and because of this, you don't get any more power. In fact, petrol companies actually put flame retardants into higher octane petrol to keep it from igniting prematurely - in effect, higher octane fuels actually contain marginally less energy per litre because they also contain other stuff.

[D-Type]

Some confusion here. I think rjbetty was asking about different brands of petrol: Shell, Esso, Tesco, etc not different grades of petrol: regular and super, normal and high octane or whatever term is used. There is diddly squat difference between different brands of regular petrol or between different brands of higher octane petrol. There is a difference between the different grades. Some high performance engines demand the higher grade and will not run well on the lower grade. The converse is not true - an ordinary engine, like in an Astra, is designed to run on regular fuel and there is no advantage in running it on the higher grade stuff. The only exception to this is if the Astra is way out of tune - I'm not technically minded but I think that means with the ignition timing advanced too far.

Interestingly, diesel can vary, but this is a temperature thing. [British] summer diesel is prone to waxing in cold weather so in winter they change the formulation. I assume that in cold climates, eg the Alaska 'hell run', the lower wax grade is standard and in the Middle East it can be either grade. Has anybody who runs a diesel car noticed whether the price of diesel goes up slightly in winter? I would expect it would.