Oil advice and recommendations here!

[mawds]

Fascinating reading, as ever - now time to ask for myself...(sorry, it's an old one again)

Engine: 1558 lotus twin-cam (1967 series 1 lotus-cortina model originally), unleaded conversion (hence slightly oversized valves), cams, fully rebuilt earlier this year, heads skimmed - 154hp at the wheels on rolling road. odd drip after a long run on valvoline racing 15W-50 - EATS oil (no smoke or anything obvious like that)

tips?

[opieoilman]

mawds said:

Fascinating reading, as ever - now time to ask for myself...(sorry, it's an old one again) Engine: 1558 lotus twin-cam (1967 series 1 lotus-cortina model originally), unleaded conversion (hence slightly oversized valves), cams, fully rebuilt earlier this year, heads skimmed - 154hp at the wheels on rolling road. odd drip after a long run on valvoline racing 15W-50 - EATS oil (no smoke or anything obvious like that) tips?

I would suggest you try the Silkolene Pro R 15w-50. The Valvoline may be dripping after a long run due to the oil heating up to a point where it is beggining to thin after prolonged use. The Silkolene Pro R is very shear and thermally stable.

Cheers

Guy.

[timbrown]

if this thread is still active ..... 3 questions in 1

I'd appreciate your comments on using ( decent quality ) motorbike oils in car engines. I hava theory that because the bike oil needs a greater shear resistance ( or something like that ) because it has to survive not only the engine but the gearbox, that it would be fine, but I'm prepared to be told different.

Also, your recommendations for Alfa 147GTA, and a Smart Roadster Brabus would be very much appreciated.

cheers

[GarryM]

Excellent posts Guy - thanks for spending the time. I have noted your comments about the Griff 500 engine but my query relates to my family car - no doubt very uncool to admit owning a Zafira 2.0 turbo (petrol), but there, done it. What would you recommend? I believe it started its life on a Vauxhall semi-synthetic (don't know the grade) but I have no problem spending a little more on a full synthetic when the oil is changed at its first service. The dealership would normally fill with semi again.

[opieoilman]

timbrown said:

if this thread is still active ..... 3 questions in 1 I'd appreciate your comments on using ( decent quality ) motorbike oils in car engines. I hava theory that because the bike oil needs a greater shear resistance ( or something like that ) because it has to survive not only the engine but the gearbox, that it would be fine, but I'm prepared to be told different. Also, your recommendations for Alfa 147GTA, and a Smart Roadster Brabus would be very much appreciated. cheers

Top quality bike oils contain ester, this is what helps with the load on the gears, you can get 4wheel oil also that contains ester. The other addative is is to allow the clutch to grip, this is not nessasary in 4wheel cars.

You can use it in a car but you are better of getting a top quality ester based 4wheel oil. You cant use 4wheel oil in a bike.

Both the Alfa and the Smart call for the same oil. You are looking for a 5w-40 full synthetic to the spec of ACEA A3. Stick with a brand as opposed to home brands as they tend to be made to a cost.

Cheers

Guy.

[opieoilman]

GarryM said:

Excellent posts Guy - thanks for spending the time. I have noted your comments about the Griff 500 engine but my query relates to my family car - no doubt very uncool to admit owning a Zafira 2.0 turbo (petrol), but there, done it. What would you recommend? I believe it started its life on a Vauxhall semi-synthetic (don't know the grade) but I have no problem spending a little more on a full synthetic when the oil is changed at its first service. The dealership would normally fill with semi again.

The Zafira calls for a 10w-40 semi or a 5w-40 full synthetic for all year round use. The semi used by vauxhall is made for them, it is ok but made to a cost so much better is readily available. If you want to change to a full synthetic stick with a brand name.

Cheers

Guy.

[timbrown]

thanks guy, it looks like the Shell helix ultra fully synth 5w40 I've got is the right choice.
Alfa recommend a synth 10w60, any obvious reasons why they might do that ? ( if it's not too much trouble )

and no, I never put car oil in the bike, that's a no-no.

thanks again

[MGBV8]

Shell and Castrol tend to use the GroupIII basestock ie not true syn, unless made in Germany?- sure Guy can add some detail on merits of different basestocks.

[opieoilman]

timbrown said:

thanks guy, it looks like the Shell helix ultra fully synth 5w40 I've got is the right choice. Alfa recommend a synth 10w60, any obvious reasons why they might do that ? ( if it's not too much trouble ) and no, I never put car oil in the bike, that's a no-no. thanks again

Alfas recomendation for this is the higher temps abroad, in this country we need lower viscosity oil due to our ambient temp.

Cheers

Guy.

[opieoilman]

MGBV8 said:

Shell and Castrol tend to use the GroupIII basestock ie not true syn, unless made in Germany?- sure Guy can add some detail on merits of different basestocks.

I will have a go, In germany it is a labeling issue. All oils produced in Germany by law have to state what it is. PAO/Ester MC/HC and so on.


“HYDROCRACKED” (HC) or MOLECULARLY CONVERTED (MC) BASESTOCKS

There are many petroleum oils available on the market that are so pure and refined, they can now be passed off as synthetics.
They are not made from true synthetic basestocks (at least not in the way that synthetics have traditionally been defined), but they have so little in common with traditional petroleum basestocks, it is really somewhat silly to classify them as petroleum oils.
Petroleum oil basestocks can be put through a super-extreme refining process called “hydrocracking”. In some cases, as in the case of one particular name-brand "synthetic" oil, these highly refined petroleum basestocks can actually be termed and sold as "synthetic".
It is completely legal for lubricants manufacturers to label these oils as "synthetic".

These are extremely high performance petroleum basestocks, but they are not truly synthetic the way that most people understand the term and will not necessarily perform to the same level as a premium synthetic oil like PAO (poly alfa olefins) or Esters.

Hydrocracking involves changing the actual structure of many of the oil basestock molecules by breaking and fragmenting different molecular structures into far more stable ones. This results in a basestock which has far better thermal and oxidative stability as well as a better ability to maintain proper viscosity through a wide temperature range - when compared to a typical petroleum basestock.

Although contaminants are still present, and these are still petroleum basestocks, contamination is minimal and performance characteristics are high. This process also can turn a wider range of crude oil stock into well-performing petroleum lubricant basestocks.

TYPES OF SYNTHETIC BASESTOCKS

Synthetic basestocks are not all the same. There are few different chemical types that may be used as synthetic basestock fluids. There are only three that are seen commonly in automotive applications:

Polyalphaolefins (PAO's)
These are the most common synthetic basestocks used in the US and in Europe. In fact, many synthetics on the market use PAO basestocks exclusively. PAO's are also called synthesized hydrocarbons and contain absolutely no wax, metals, sulfur or phosphorous. Viscosity indexes for nearly all PAO's are around 150, and they have extremely low pour points (normally below –40 degrees F). Although PAO's are also very thermally stable, there are a couple of drawbacks to using PAO basestocks. One drawback to using PAO's is that they are not as oxidatively stable as other synthetics. But, when properly additized, oxidative stability can be achieved.

Diesters
These synthetic basestocks offer many of the same benefits of PAO's but are more varied in structure. Therefore, their performance characteristics vary more than PAO's do. Nevertheless, if chosen carefully, diesters generally provide better pour points than PAO's (about -60 to -80 degrees F) and are a little more oxidatively stable when properly additized.
Diesters also have very good inherent solvency characteristics which means that not only do they burn cleanly, they also clean out deposits left behind by other lubricants - even without the aid of detergency additives.
They do have one extra benefit though, they are surface-active (electrostatically attracted to metal surfaces), PAO’s are not “polar”, they are “inert”.

Polyolesters
Similar to diesters, but slightly more complex. Greater range of pour points and viscosity indexes than diesters, but some polyolester basestocks will outperform diesters with pour points as low as -90 degrees F and viscosity indexes as high as 160 (without VI additive improvers). They are also “polar”.

Other synthetic basestocks exist but are not nearly as widely used as those above - especially in automotive type applications. Most synthetics on the market will use a single PAO basestock combined with an adequate additive package to provide a medium quality synthetic lubricant. However, PAO basestocks are not all the same. Their final lubricating characteristics depend on the chemical reactions used to create them.

Premium quality synthetics will blend more than one "species" of PAO and/or will blend these PAO basestocks with a certain amount of diester or polyolester in order to create a basestock which combines all of the relative benefits of these different basestocks.

This requires a great deal of experience and expertise. As a result, such basestock blending is rare within the synthetic lubricants industry and only done by very experienced companies. In addition, although such blending creates extremely high quality synthetic oils, they don't come cheap. You get what you pay for! Or do you?

Cheers

Guy.

[900T-R]

Classic Saab 900 Turbo (1985)

Engine: 1991 900 block; forged Cosworth pistons, oil cooling jets, crank and rods shotpeened; rotating assembly weighted & balanced; 4,600 kms after build
Head: 2000ish 9-5; gasflowed; bigger valves; 2,000 kms after installation
Turbo: upgraded Garrett T03; watercooled bearing housing; 360 degree thrust bearing

Ran competition running-in oil for first 2 hrs; then 10 or 15W40 Valvoline mineral for first 1.500 kms; then Valvoline Synpower 'fully synthetic' (er, hydrocrack base oil) 5W50

'Weekend' car for road and occasional track use; runs 1.3ish bar (more like 1.26) max boost, output 281 hp @6,000 rpm. Rev limit 7,000.

[900T-R]

Oh, I'd also like recommendations regarding gearbox oils for a 1991-93 Saab 900 transaxle (longitudinally mounted under car). Torque load is a bit beyond what the gearbox is designed for I'm afraid, and even though I bought it as a recon box with allegedly all new synchros and bearings the synchro on 5th gear has always been a bit iffy.

[edit: currently running Castrol Syntrax Universal 75W90]

>> Edited by 900T-R on Wednesday 29th September 15:38

[MGBV8]

The Shell blends appear to be

5W-40 ........... gr. III (or gr.II+ ?)
5W-30 ........... PAO + gr III (or PAO + gr.II+ ?)
5W-30 AB ...... gr.III
5W-30 diesel .. gr.III + PAO + Esters
0W-40 ........... PAO
10W-60 ......... 1). PAO, 2). Esters + PAO

About time for some clear labelling in UK!

[opieoilman]

900T-R said:

Classic Saab 900 Turbo (1985) Engine: 1991 900 block; forged Cosworth pistons, oil cooling jets, crank and rods shotpeened; rotating assembly weighted & balanced; 4,600 kms after build Head: 2000ish 9-5; gasflowed; bigger valves; 2,000 kms after installation Turbo: upgraded Garrett T03; watercooled bearing housing; 360 degree thrust bearing Ran competition running-in oil for first 2 hrs; then 10 or 15W40 Valvoline mineral for first 1.500 kms; then Valvoline Synpower 'fully synthetic' (er, hydrocrack base oil) 5W50 'Weekend' car for road and occasional track use; runs 1.3ish bar (more like 1.26) max boost, output 281 hp @6,000 rpm. Rev limit 7,000.

That sounds like quite a Saab you have yourself there, my brother in law is into his Saabs, he has a 99Turbo.

For yours I would suggest a top quality synthetic only as you will want to protect all those mods you have done. Look at a PAO or Ester based synthetic around the 5w-40 or 10w-50 grade.

The 5w-50 you are using sounds to be an ideal grade however a lot of manufaturers are phasing this out. The reason for this is the amount of VI improver needed to keep the oil in grade throught its viscosity range. The less VI improver in an oil the better.

For the gearbox it is only allowed to use mineral oil, infact it uses engine mineral oil of around the 10w-40 grade, strange but true.

Hope this helps.

Guy.

[opieoilman]

MGBV8 said:

The Shell blends appear to be 5W-40 ........... gr. III (or gr.II+ ?) 5W-30 ........... PAO + gr III (or PAO + gr.II+ ?) 5W-30 AB ...... gr.III 5W-30 diesel .. gr.III + PAO + Esters 0W-40 ........... PAO 10W-60 ......... 1). PAO, 2). Esters + PAO About time for some clear labelling in UK!

I agree, Gernamny is the only place who has to say it does exactly what it says on the tin! If the labelling was precise there would be a lot less confusion.

Cheers

Guy.

[900T-R]

opieoilman said:

[Hope this helps. Guy.

Absolutely, thanks a bunch!!

[GavinPearson]

I have a Sierra XR4x4. Now pick yourself up off the floor from the uncontrollable laughter.

I live in Detroit. It gets cold in the winter, typically 0 Farenheit - about -20 Celcius. If I am giving the engine a sound thrashing once it's warmed up, what grade should I use? My fear is the oil has a consistency of jelly when cold and will cause problems with the oil filter.

[opieoilman]

GavinPearson said:

I have a Sierra XR4x4. Now pick yourself up off the floor from the uncontrollable laughter. I live in Detroit. It gets cold in the winter, typically 0 Farenheit - about -20 Celcius. If I am giving the engine a sound thrashing once it's warmed up, what grade should I use? My fear is the oil has a consistency of jelly when cold and will cause problems with the oil filter.

Gee there cant be that many Sierras in Detroit!

I would go for a good quality PAO or Ester 5w-40, this will go as low as -30 with ease. When the climate warms up you could move to thicker grade around a 10w-50.

A good PAO/Ester 5w-40 will be able to take a good pasting when warm.

I do not know what is available out where you are but look at Mobil 1 and Redline etc.

Cheers

Guy.

[Kawasicki]

Make BMW
Model 635CSi
Year 1987
Engine size and type 3.5l M30 Straight 6
Any significant modifications No
Brand and viscosity currently used 15W50 Mobil 1

The is driven quite hard...once fully warmed.

Any advice much appreciated.

Shane

[opieoilman]

Kawasicki said:

Make BMW Model 635CSi Year 1987 Engine size and type 3.5l M30 Straight 6 Any significant modifications No Brand and viscosity currently used 15W50 Mobil 1 The is driven quite hard...once fully warmed. Any advice much appreciated. Shane

Shane,

You are pretty much on the nail with this one. The old raw straight six likes the thicker oil of the 10w-50/15w-50 grade. You can use mineral semi or full synehtic.

As you are using Mobil 1 15w-50 you cant really do much better as Mobil 1 is a top PAO synthetic. The only way you could go better is to use a PAO/Ester synehtic, as esters are "polar"

Cheers

Guy.