to wonder who buys the more expensive fuel

[barneyblues]

The one that's higher octane and costs about 10-15p more per litre.

Why would you buy it? Surely it doesn't make that much difference?

Isn’t Redex for cleaning out engines though?

@Leflic

That or just drive the car more. People mainly do short journeys which doesn't give your car a chance to warm up. So the engine can't clear itself out. Have to replace parts more often because of that. I've had my car 3 years now, bought it when it was 9 years old. I've almost tripled the mileage it had on it when I bought it, and apart from the usual things like tyres, lights and brakes I've replaced nothing. I'm pretty sure unless the previous owner replaced the exhaust that it's the original one on the car. Don't use expensive fuel either, just Tesco normally. Oh I don't take it to garages either for services, we do the services ourselves because garages do a crap job. It's never a full, proper service, you're lucky if they change the oil filter. Certainly not going to change the other filters. And you get charged hundreds for the privilege of them checking your horn and lights. Pretty sure I can do that myself. I can buy the parts on ebay for £40, buy the oil and job done. It is amazing what garages will sting you for.

When we drove sports cars we opted for the better quality fuel.

My dh does , he has a high performance car and quality of petrol definitely makes a difference

I did by accident last week (unfamiliar petrol station with different grades at different pumps). Made no difference whatsoever to fuel consumption. Just made slightly more pollution.

Higher octane fuel with its additives allows the engine to run at higher rpm / higher temperature so burns off impurities and, combined with the additional detergents, you should get a cleaner engine. Worth putting a tank through every now and then.

what about very old cars? would that work

with the oil i understand it really doesnt matter with old cars.

With old (classic) cars they should run better on higher octane but you need to watch out for the ethanol content of the fuel - you need to minimise it as older engines don’t cope well with it. If designed for leaded fuel you’d need to add a lead replacement too.

thank you continuity

Our friends have a BMW X5 and have to use the expensive stuff (and lots of it!) we have a much cheaper SUV so I’ve only used it by accident 😂. I thought for a while that I got more MPG using ‘proper’ petrol station fuel rather than supermarket, but after extensive testing, I don’t.

@SimonJt the majority of cars (modern or not) haven’t been remapped.

Whether or not the car has been remapped is irrelevant. Most modern petrol engines have a knock sensor fitted that will enable the ignition timing to be automatically advanced or retarded to make best use of the octane rating of the fuel being used.

Unless this is deliberately disabled, it will work whether the car has been remapped or not.

I used to, in my last car. I did notice if I put the cheaper supermarket fuel in the engine didn’t feel as smooth. My new car is electric so no longer applicable, but DH still in a petrol. He puts in cheapest he can find and says he doesn’t notice the difference, though his car is a lot newer than my old one so there’s probably something in that, too.

Nah that extra 15p 20p isn't cost effective for us. Car's are expensive enough with tax, insurance, MOTs, repairs etc. I don't need our engine to run better, just want to get from A to B in a relative safe manner.

I am slightly confused by people who have been told they have to use it. I'v had a variety of expensive cars and never been told anything beyond 'remember it's a diesel'.

I think it depends on the engine. It's more on the compression ratio than on the overall power or cost.

I am slightly confused by people who have been told they have to use it. I'v had a variety of expensive cars and never been told anything beyond 'remember it's a diesel'.

If it is a diesel it won't like high octane fuel. You don't have to use high octane petrol in a modern car because the engine will automatically adapt to a lower octane. However, it is likely to perform better and give more mpg using the high octane fuel.

If you have a twenty year old Porsche (or intend to keep your Porsche for 20 years) then it makes a difference.,

My 22 year old sports car won't run on cheaper fuels. The manufacturer recommends 98 octaine or higher so I use Shell V power unleaded as much as possible and if I cannot find a Shell station I have to use the highest octaine fuel the garage has. My car does not like lesser octaine fuel at all, I can feel it pinking as soon as I try to accelerate.

@Reginabambina
LOL are you sitting behind me?

@eyemask you haven't had properly expensive cars if they're diesel I'm afraid. That's why you're confused, what you think is an expensive car is in a different league to what some of us are talking about.

Most of my cars have higher octane specified by the manufacturer. Bear in mind this is related to engine compression, the timing curve and other factors. The high performance engines are set up to run optimally on a given (higher) octane rating. So if you have a Nissan micra then don’t bother with high octane fuels.

But I get the Tesco 99 octane as it’s far less expensive than the Shell for the same octane rating and it’s also cheaper than BP 96 octane.

If you have a twenty year old Porsche (or intend to keep your Porsche for 20 years) then it makes a difference

This!

@tiggertogger do you want to enlighten me about what cars you are talking about before making assumptions. My comment was relating to pp about a friends BMW X5 which did surprise me.
FWIW I can totally understand old cars requiring a little more tlc.

what you think is an expensive car is in a different league to what some of us are talking about.

Fuck me I thought I had mistakenly logged on to pistonheads for a minute there. What a pompous statement!

what you think is an expensive car is in a different league to what some of us are talking about