Hi all,

I'm driving Octy I with 1.8T engine. Still stock 150 HP, but I'm considering making modifications to the engine to reach a healthy 180-190 HP.

To this end I saw at my local car parts shop Mobile 1 Rally Formula motor oil 5W50. The price was quite reasonable.

Would you recommend this motor oil, or some other oil for turbo engines, or instead should I stick to the usual 10W40 Castrol SLX Professional? I had Castrol for the last three years and I have no objections.

Cheers

Marko

I would say use a good quality oil that is the correct specification for the engine, i now use mobil one but there are a few good oils around for you engine but you'd be better off sticking with the manufacturers recommendations.

speak to opie oils if your fancying a change and want to know more

I wouldn't recommend using the 5W-50, because it's too thick, and will give you problems with hydraulic tappet pump-up at high revs on a hot engine. That can lead to burnt or dropped valves.

Does the Castrol actually meet the latest VAG500 series petrol oil specification?

Does the Castrol actually meet the latest VAG500 series petrol oil specification?

Good point, apparently it does. As far as I know Castrol SLX Pro or Shell Helix Ultra are both acceptable lubricants for VAG petrol engines.

So for 1.8T you would recommend less dense, less heavy oil in line with 10w40 grade?

Although oils for turbos working in hard conditions go as far as 10w60?

There have been cases over here of people destroying engines (mostly Ford rather than VAG) by using too high viscosity oils in hydraulic tappet engines. From what you say I'd be happy with the Castrol, although my dealer has always used Shell Helix on my car.

FWIW if you only want to reach 180-190 bhp you can do that with just a map.

The engine would run best on the correct oil as per the manual with more frequent changes rather than thick oil.

OK guys, so the answer is marginally yes but better no

I have been using this stuff on my remapped VRS.

Fuchs TITAN SUPERSYN 5W-40 High Performance, Fully Synthetic, Engine Oil.

Good value.

If you go to this site it will advise you some variants of oil for your car.

Opie Oils the oilman for engine oil, car oil, motorbike oil, gear oil, motor oil, brake fluid

I found it useful.

A lot of guys I know, some with remapped engines, are using LIQUI MOLY. Comes pretty cheap and apparently there are no ill side effects.

A lot of guys I know, some with remapped engines, are using LIQUI MOLY. Comes pretty cheap and apparently there are no ill side effects.

Apart from the fact that it allegedly blocks the pores on the oil filter and causes the oil to exit the filter via the bypass plug meaning the oil is leaving unfiltered.

IMHO best avoided.

Really? :eek: Sounds bad to say the least. :thumbdwn:

If these additives where so good I imagine the oil makers would be including them in their formulas already. The fact they don't says it all to me.

If these additives where so good I imagine the oil makers would be including them in their formulas already. The fact they don't says it all to me.

And if they wernt putting it in the oil then car manufacturers would be promoting them as it would mean less failures for them to deal with.

I bought 4 litres of Castrol Edge 5W-30 last night for £35.99 in Halfords (with trade card - £45 normally).

It's what I've always used in the car since I've had it, and this will be my fourth change on it. Great stuff, as I've never had problems, and the engine doesn't use any oil.

5W-50 is going to be way too thick surely, and I wouldn't bother with additives as others have said. Try the Castrol website for what you should be using.

Bear in mind the the manufacturers recommendations for oil viscosity are for new engine with all of the cleareances nice and tight. As the mileage increases, so do the clearances and so a thicker oil can be helpfu in keeping the engine quiet. My 968 is supposed to run 5w40 oil. It has just over 100k on the clock now and when I filled it with oil of the correct viscosity, the hydraulic tappets rattled and I had various other unpleasent and un-Porsche like noises coming from the engine. I drained this out on the recommendation of a respected Porsche specialist and refilled with Mobil 1 15w50. The tappets now quieten down almost immediately and stay quiet and now more odd knocks or rattles.

BTW, after the previous post I asked around about Liqy Moly (LM). It turns out that LM has VAG505 certificate and that is it the original factory oil "first fill" in some MGs and BMWs. Also, LM additives have TUV certificate. Therefore I don't know how could they got all this if they are so bad?

Their oils might meet the spec, but I'd not let their additives near any car I owned.

While some oils will have Molybdenum Disulphide in them as a thin film anti wear additive, that doesn't mean it's a good idea to dump a pile of the stuff in any old oil.

Basically the additives are tailored to the oil and IIRC MoS2 is usually used in gear oil. In certain other cases it will cause problems preventing things working as designed.

It's not exactly a small item:

http://www.fhi-berlin.mpg.de/~hermann/Balsac/BalsacPictures/SSDfig159.gif

If you think about it, dumping a load of that in the oil, you stand a good chance of it all ending up in the oil filter before it's had a chance to coat anything and just blocking up the filter.

These are of course just my own thoughts, and you're welcome to do as you please.

Edited 20 July, 200916 yr by cheezemonkhai

Using 5W50 oil could be justified when an engine is at extremely elevated temperatures all the time, i.e. race track conditions at or near full power. The other use for this oil may be when oil consumption of standard grades become excessive (due to wear).

Otherwise the increased drag will guarantee accelerated wear, a bigger fuel bill, and less power!

Todays modern engines rely on the greater flow rate of thinner oils to give better and evenly distributed cooling.

I would have said it's better to stick with an oil that's correct for your car.

You're handbook will state the correct code.

Cheers

I've got a mate with two Citroen C1s. He has a diesel model and his wife has a petrol. He lives in Cornwall and drives 40 miles each way to work and back every day. He manages to achieve a staggering 96mpg, and absolutely swears by Mobil 1 engine oil......

And the correct mobil1 for this car would be mobil1 ESP (VW504/507) or another VW spec oil from them.

I bought 4 litres of Castrol Edge 5W-30 last night for £35.99 in Halfords (with trade card - £45 normally).

You must be on a variable service then as that rating is not recommended for fixed services.

You must be on a variable service then as that rating is not recommended for fixed services.

I change the oil every 10k miles.

Castrol recommend Edge 5W-30 for both QG1/Variable and QG2/Fixed. (http://www.castrol.com/castrol/iframe.do?categoryId=9024084&contentId=7044829)

If the oil is suitable for a long-life (20k) service schedule, then why wouldn't it be more than suitable for a normal service (10k) interval?

The advantage is that I know my oil will be good for 20k, but to be on the safe side I change it at 10k.

It meets VW 504 00/507 00 whatever that is. Engine Oil and Lubricants Castrol UK - Castrol EDGE 5W-30

If you think I should be using something else then please let me know!

P.S. I'm still loving the Weitecs Bowders!

I change the oil every 10k miles.

Castrol recommend Edge 5W-30 for both QG1/Variable and QG2/Fixed. (http://www.castrol.com/castrol/iframe.do?categoryId=9024084&contentId=7044829)

If the oil is suitable for a long-life (20k) service schedule, then why wouldn't it be more than suitable for a normal service (10k) interval?

The advantage is that I know my oil will be good for 20k, but to be on the safe side I change it at 10k.

It meets VW 504 00/507 00 whatever that is. Engine Oil and Lubricants Castrol UK - Castrol EDGE 5W-30

If you think I should be using something else then please let me know!

P.S. I'm still loving the Weitecs Bowders!

Interesting info. I know Fuchs Oil recomends 10W-40 for Fixed changes. As I change my oil every 5k(lot of short journeys) not sure what would work best for me.

Great you still loving the Weitecs.

I have been using Fuchs Titan GT1 which is 507.000 but i change it every 10k.I need to order some more while Opie have a good offer on.