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Defcon5

Original Poster:

4,552 posts

75 months

[news] 
Friday 21st September 2012 quote quote all
Is Petronas oil any good?

It's on offer at less than £20 for 4l of VAG507/ll04 5w30, which seems a bargain

Pumaracing

1,414 posts

91 months

[news] 
Friday 21st September 2012 quote quote all
It's supposed to provide very good engine protection - especially against Dementors.

Evoluzione

1,708 posts

127 months

[news] 
Saturday 22nd September 2012 quote quote all
Pumaracing said:
It's supposed to provide very good engine protection - especially against Dementors.
Interesting use of a word taken (so I have just found out) from a Harry Potter book:

"A Dementor is a Dark creature, considered one of the foulest to inhabit the world. ... "one who afflicts with great suffering"

Although I have to say, I do prefer the one found in the Urban dictionary:

" A girl who gives really good head, but her very annoying personality slowly sucks away your soul."

smile

Defcon5

Original Poster:

4,552 posts

75 months

[news] 
Saturday 22nd September 2012 quote quote all
Pumaracing said:
It's supposed to provide very good engine protection - especially against Dementors.
If that's not a typo it's gone way over my head

Pumaracing

1,414 posts

91 months

[news] 
Saturday 22nd September 2012 quote quote all
In Harry Potter you protect yourself against Dementors with a Patronus charm.

Ok, I'll get me coat.
Advertisement

Defcon5

Original Poster:

4,552 posts

75 months

[news] 
Saturday 22nd September 2012 quote quote all
Sorry, never read them!

Anyone have an opinion on the original question

Pumaracing

1,414 posts

91 months

[news] 
Saturday 22nd September 2012 quote quote all
If you go to Tesco you can get 4l of 5/30 oil for £5 if they have any left.

PaulKemp

400 posts

29 months

[news] 
Saturday 22nd September 2012 quote quote all
From that response I take it there is little difference in engine oils?
Would this be worth further discussion?
I have always gone with the cheaper stuff, changed frequently with a good filter

Pumaracing

1,414 posts

91 months

[news] 
Sunday 23rd September 2012 quote quote all
As long as oil meets the spec the engine manufacturer specifies I doubt it matters a jot to most drivers what brand of can it comes in. The worst oil you can buy today is probably ten times as good as the best oil from 40 years ago and people still managed to make engines outlast the rest of the car back then.

The Tesco 5w/30 I saw the other week isn't just cheap because it's a crappy old spec mineral oil, it's a semi-synthetic to API SL spec made by Tetrosyl designed specifically for engines like my Zetec and would normally be three or four times the price. I assume they're still making a profit at £5 for 4 litres but god knows how. I bought a car load of it and once the special offer is over I'll knock it out on Gumtree or Ebay for £10 or £15 a can.

Maybe a fully synthetic API SN spec oil costing £10 a litre or more is better still but how long does anyone need their engine to last? Not much point in trying to make it last twice as long as the chassis before that rusts away.

Back in about 1990 when synthetics were fairly new and Mobil 1 the best known of these I knew someone who worked in an oil test lab. They'd dyno engines for specified periods under set loads and measure components to microns before and after to test for wear. Even back then they were getting no detectable engine wear over the test period with Mobil 1. I really wonder just how much better the very latest oils are and whether we even really need them unless you're aiming for 500,000 mile engine life.

The other thing about modern engines is they don't tend to wear much in the first place unless you really abuse them and it's the swarf from initial wear that causes a chain reaction into terminal wear. Old engines like the CVH and to a lesser extent the Pinto had cams that wore out like buggery at the best of times because they weren't properly designed. It made little difference what oil you had in there because it would be full of microscopic metal particles anyway. By 70k to 100k miles the rest of the engine would be completely shagged. I regularly used to see 5 thou or more bore wear on even medium mileage CVH donor engines I was rebuilding into race motors. I once measured 8 thou on a 70k mile CVH engine. Modern chill cast cams in twin cam OHC engines just don't wear and create swarf and then nor do the bores or crank bearings wear either. Modern low tension thin piston rings also create much less bore wear than old style thick rings.

I can strip down 100k mile modern engines and still see the cross hatching in the bores. Having to get cranks reground is almost a thing of the past too. I'd say that it's valve guides and stem seals that go before anything else in most engines. Mainly engines with cheap grades of bronze valve guides which the continentals are very fond of for some reason and which only lasts a fraction of the life of cast iron and sintered guides. Peugeot, Citreon, BMW, VW and others often use crappy grades of manganese bronze for valve guides whereas the Japs and Ford tend to stick with ferrous guides. I've never even seen a really shagged iron valve guide in a Ford CVH even when the rest of the engine was toast. However the manganese bronze guides in VW Golf or Peugeot 205 engines often wouldn't last a single race season with high lift cams.

In most modern engines though the main largish metal bits last for ever. I suspect they would still last for ever no matter what oil you put in there.

The Zetec engine in my Focus has everything in it spot on for minimum wear. Iron guides, chill cast cams with light valve springs and thin piston rings. They just don't wear out - period. As long as it has oil in it of some sort or other, to the max mark on the stick and not too black and manky I couldn't care less what make it is. It'll outlast me.

dhariwab

396 posts

35 months

[news] 
Monday 24th September 2012 quote quote all
Thank you for that great info smile

Defcon5

Original Poster:

4,552 posts

75 months

[news] 
Monday 24th September 2012 quote quote all
I couldn't bring myself to buy Tesco branded oil.

I appreciate you are rather knowledgeable in this field pumaracing, but I couldn't live with myself!


Pumaracing

1,414 posts

91 months

[news] 
Monday 24th September 2012 quote quote all
It isn't Tesco branded. It's the same as this.

http://compare.ebay.co.uk/like/300678814032

Defcon5

Original Poster:

4,552 posts

75 months

[news] 
Tuesday 25th September 2012 quote quote all
That's for the Ford Zetec engines isn't it? I need something LL04 and VAG507 approved

Berw

1,673 posts

89 months

[news] 
Friday 28th September 2012 quote quote all
It was/is made in Germany, I assume Eurapean stock still is, I wont make alligations or subjective statements just facts, (check my profile to guess why) My Esprit engine lasted a half lap of Sepang on fully synthetic, threw a couple of main bearings and sized a cam in turn 5 after a change from Mobil 1, I spoke to the technical people they refused to give me info on the oil molecular structure that Castrol freely publish saying it was company confidential, I said Ok fine if I don't have info to make a judjement I'll just never use it again and I dont in my race cars or the Porsche its Ok in the Peradua. (the petrol is great both the 95 and the 102 race fuel,had it on the Dyno and at least as good as Shell on power but without the additives that stay and block jets when the benzine evaporates off).

Defcon5

Original Poster:

4,552 posts

75 months

[news] 
Friday 28th September 2012 quote quote all
If it has VAG 507 approval it must be pretty good though - its quite strict isn't it?

SuperchargedVR6

1,066 posts

104 months

[news] 
Friday 28th September 2012 quote quote all
Circuit racing isn't part of VAG-507 approval though wink

If there is any doubt, there is no doubt. If you value your engine, stick to the tried and tested brands.

Defcon5

Original Poster:

4,552 posts

75 months

[news] 
Friday 28th September 2012 quote quote all
Engine failure after half a lap on new oil though? Far more likely to be an issue that was already present.



Berw

1,673 posts

89 months

[news] 
Sunday 30th September 2012 quote quote all
Defcon I have more experince of it than any one on here and as I say I would not use it, you asked you got an answer you decide,

Pumaracing

1,414 posts

91 months

[news] 
Sunday 30th September 2012 quote quote all
Defcon5 said:
That's for the Ford Zetec engines isn't it? I need something LL04 and VAG507 approved
Well maybe you think you do but a better place to start would be to understand just what has been happening to oil specifications over the last 20 years and why. You might suppose that the driving factor in each new oil spec that comes out is providing better engine protection. It's actually almost the reverse. Fuel economy and catalytic convertor life are the main factors and these mandate the use of thinner oils and also those with less anti wear additives in them.

The best anti wear additives, particularly for flat tappet cams, are zinc and phosphorus compounds and these have been added to oil for many decades in the form of an additive called ZDDP. However it reduces catalytic convertor life somewhat although nothing like as much as tetra ethyl lead in leaded petrol does.

To make engines last without ZDDP in the oil requires much lower cam to follower stresses than you'd find on old 2V engine designs so manufacturers have had to turn to 16v engines with lighter valves and valve springs and also to the use of roller cam followers rather than flat tappet ones. That has enabled the API oil specs to incrementally reduce the ZDDP concentrations since the 1990s.

If you want the best engine protection you almost certainly don't automatically just want the latest oil spec. In fact an old SH or SJ oil will be a much better bet for an old engine design than the latest SN spec. For race use you'd also ideally not want the thin oils for road use like 0-30 and 5-30 grades which are great for cold starts but less good when the oil is stinking hot and you'd probably be well advised to use a ZDDP additive package unless you can find a race specific oil blend with lots of that in it anyway.

So it isn't that progressively better and better oil has made engines last longer. It's more that modern engine designs that wear less have allowed the use of oil that resists wear less well but gives slightly better cat life and fuel consumption.

For most modern 16v road engines much of this is irrelevant. You simply won't be able to use them hard enough or get the oil hot enough on the road for the oil make or spec to matter much and engine life will be way longer than most people keep their cars for no matter what oil you put in them. So when I find a decent spec semi synthetic at £5 for 4 litres I'll use that quite happily in just about anything and let the people who want to pay 10 times as much for oil do their own thing if it makes them happy.

Pumaracing

1,414 posts

91 months

[news] 
Sunday 30th September 2012 quote quote all
Berw said:
Defcon I have more experince of it than any one on here and as I say I would not use it, you asked you got an answer you decide,
I doubt if you have anything like as much experience as me and you certainly don't seize cams up that quickly without there being a catastrophic oil supply failure such as a broken pump drive or serious oil surge under cornering. It's vanishingly unlikely that your problems were solely to do with the make of oil you used.
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