Unleaded V Super Unleaded

[DevonMark]

Is it worth filling up with Super Unleaded rather than standard? Does it make any difference?

I have a 1989 1.9l petrol engine. Would be happy to spend extra on the fuel if it was good for the van.

[AdrianC]

Is it worth filling up with Super Unleaded rather than standard? Does it make any difference?

I have a 1989 1.9l petrol engine. Would be happy to spend extra on the fuel if it was good for the van.

If it's not pinking on 95, then there's no point whatsoever going to 98.

[mark]

IMHO
you will (maybe) get a better return mpg wise,i try to stay away from cheaper super market fuel and only ever use super unleaded in mine, being a dj it needs full fat.

at our volvo's last service the mechanic said to treat it to super every couple of tank fulls and avoid supermarket s***.

i am not a mechanic,petrol pump attendant or an oil shiek and only have personel experience to go on as a petrol buyer and polluter.

mark

[DevonMark]

Thanks chaps.

Quick question - what is 'pinking'?

Looks like there's quite a split opinion about whether premium's worth it. I guess I'll try it at some point to see if I notice a difference. It can't do any harm,
can it?

[mark]

pinking is preignition caused by low quality fuels. it will cause no damage and will do only good

mark

[Oldiebut goodie]

it will cause no damage and will do only good

mark

Really?
From the ubiquitous wikipedia:

If detonation is allowed to persist under extreme conditions or over many engine cycles, engine parts can be damaged or destroyed. The simplest deleterious effects are typically particle wear caused by moderate knocking, which may further ensue through the engine's oil system and cause wear on other parts before being trapped by the oil filter. Severe knocking can lead to catastrophic failure in the form of physical holes punched through the piston or cylinder head (i.e., rupture of the combustion chamber), either of which depressurizes the affected cylinder and introduces large metal fragments, fuel, and combustion products into the oil system.

[DevonMark]

Cheers Mark. Will treat my van to some premium soon!

[DevonMark]

it will cause no damage and will do only good

mark

Really?
From the ubiquitous wikipedia:

If detonation is allowed to persist under extreme conditions or over many engine cycles, engine parts can be damaged or destroyed. The simplest deleterious effects are typically particle wear caused by moderate knocking, which may further ensue through the engine's oil system and cause wear on other parts before being trapped by the oil filter. Severe knocking can lead to catastrophic failure in the form of physical holes punched through the piston or cylinder head (i.e., rupture of the combustion chamber), either of which depressurizes the affected cylinder and introduces large metal fragments, fuel, and combustion products into the oil system.

I think mark meant that premium petrol would do no harm, not that pinking would do no harm :S

[AdrianC]

I think mark meant that premium petrol would do no harm

Except to your wallet.

Pinking sounds like "metallic rice krispies" - and tends to occur around mid revs, heavy load. Climb a hill, foot flat, with ~2500-3000 rpm. STEREO OFF, window open. If it's pinking, you'll hear it if you listen carefully.

The DJ in our van doesn't pink. We run it on 95.

[mark]

full fat fuel will cause no harm, pinking will nack it.

mark

[AdrianC]

full fat fuel will cause no harm, pinking will nack it.

Time it so that it pinks on 98 (or even 100), and the pinking will knacker it, too.
Time it so that it doesn't pink on 91 (it still exists in some places), and it'll run safely on it. If slowly.

For me, the problem with 98 is that it's really not that widely available. Yes, it costs more - but if you're gasping for fuel in the a*** end of nowhere, and there's no 98 available, what then?

[mark]

IMHO
you will (maybe) get a better return mpg wise,i try to stay away from cheaper super market fuel and only ever use super unleaded in mine, being a dj it needs full fat.

at our volvo's last service the mechanic said to treat it to super every couple of tank fulls and avoid supermarket s***.

i am not a mechanic,petrol pump attendant or an oil shiek and only have personel experience to go on as a petrol buyer and polluter.

mark

its needs full fat fuel as its still timed as it left the factory.

mark

[AdrianC]

its needs full fat fuel as its still timed as it left the factory.

Despite modern fuel being very different to that back in 1991?

[mark]

full fat fuel will cause no harm, pinking will nack it.

Time it so that it pinks on 98 (or even 100), and the pinking will knacker it, too.
Time it so that it doesn't pink on 91 (it still exists in some places), and it'll run safely on it. If slowly.

For me, the problem with 98 is that it's really not that widely available. Yes, it costs more - but if you're gasping for fuel in the a*** end of nowhere, and there's no 98 available, what then?

i started my reply with IMHO so i didnt get embroiled in one of your im right your wrong slanging matches, you seem to get no end of pleasure from them.
personally i try to stay away from the a*** end of anywhere.
why would i time it inncorrectly and run it on 98 and why would i time it to run on 91. if i needed to run it on inferior fuel i am equiped to make it happen.

ok here goes, if timed correctly super unleaded will cause no harm, though if you so wish to change the timing, advance or retard the timing to such an extent that it pinks then it will knacker your engine.

mark

[AdrianC]

personally i try to stay away from the a*** end of anywhere.

We're all different. That's the whole reason we bought the van.

ok here goes, if timed correctly super unleaded will cause no harm, though if you so wish to change the timing, advance or retard the timing to such an extent that it pinks then it will knacker your engine.

I think you're misunderstanding me here. If it's pinking, that will damage the engine, no matter what octane fuel it's on. If it's not pinking, pinking cannot damage the engine, no matter what octane fuel it's on.

To me, "timing correctly" is timing it so it DOESN'T pink on the fuel you use. Start from the factory settings, and if it pinks, retard it until it doesn't.