Oil & Cold Starts - Good Advice from Opie Oils

[oilman]

At this time of year, it’s beneficial to use an oil that has good cold start flow properties as it will get to the parts of the engine that need it far more quickly when you turn the key on those sub zero mornings.
The "w" number which means winter is the key here and the lower it is the better cold start performance the oil will have.
A 15w or 20w rated oil will struggle to get around the engine in very cold temps and we would strongly recommend using a 10w, 5w or 0w for better cold start performance.
It is a fact that around 90% of all engine wear occurs on cold start because the oil is at its thickest. The colder it gets the thicker the oil becomes and this affects the rate of flow which affects the rate of wear.
These numbers help to explain the oils thickness and therefore cold flow performance at various temperatures.
Grade.................At 0C.................At 10C..............At 100C
0W/20.............328.6cSt...............180.8cSt.... ........9cSt
5W/40.............811.4cSt...............421.4cSt.... ........14cSt
10W/50............1039cSt...............538.9cSt...... ......18cSt
15W/50.............1376cSt..............674.7cSt...... ......18cSt
20W/50.............2305cSt...............1015cSt...... ......18cSt
Centistokes (cst) is the measure of a fluid's resistance to flow (viscosity). It is calculated in terms of the time required for a standard quantity of fluid at a certain temperature to flow through a standard orifice. The higher the value, the thicker the oil.
Winters in the UK are fortunately not too cold but, below zero temperatures are regular features in some parts of the country.
Compare the thickness of the oil at 0degC and 100degC and you will see the big difference.
Just something to consider on those frosty mornings.
The Opieoils Team.

[Lucky]

Cool, some useful info there.

[scoobaru]

5w/40 it is then? Looks the best

[Jimmy@JSEngineering]

I'd go 10-60 all year round, but they havent got it listed.

[asperformance]

its far more important that you use the correct grade for your 'use' than simply using the "thinnest" oil available.............

far more likely to cause damage by running too light an oil than a few cold starts IMO and experience

[scoobaru]

Getting an oil change on sat but dont know what to go for?

I have a bug eye wrx with vf30 decat up and down, 3" all the way through exhaust and pinks, mapped to over 300?

5w30 as the spec insists?
5w40 as opie?
10w60 as asperformance?

Im confused??/

Please help if someojne has the same spec with the winter looming.

Cheers people.

[asperformance]

its far more important to have an oil that matches your "spec/use" than worrying about the odd cold start as even using even a 15w oil in the UK will generally have no long term effect due to the lack of massive sub zero temps

[Jolly Green Monster]

agree 100% with Asperformance.

Simon

[scoobycoops]

Asp is correct and it is very easy to change your warm up technique/period in cold weather.
Rob's tips:
1. Gently does it a bit longer.
2. Just don't red line so soon in winter!!!
3. Use that time it takes to scrape your windows to run it on tick over and get the heater warm.

[scoobaru]

10w/40 I think for to tmoz.