will check today what it's running when really hot off to the farm lanes we go

 

Stick with millers 10w50, thats what I ran year round with my old 523bhp classic

 

Yeah the oil/water heat exchanger alone is better for winter warm ups, which is more what it is designed for.

 

Interesting thread, I have also been wondering about oil temps and what to run recently.

So I am currently running 15/50 in my newage wrx running around 330bhp, this is for weekend and track days, car wont get used much in the winter and is kept in a garage, should I run a thinner oil in the winter?

Also what is too hot for oil? I got up to around 120 (before I backed off) running 10/50 on track so fitted an oil cooler but havn't yet fully thrashed it on a comparable track day to do a comparison?

 

can of worms..............

but in simple terms for the weather conditions we have in the UK there is no reason to be swapping between winter & summer grades............
and for a fully forged motor used in arduous road use and expected to last for miles then a 10w60 will cause no detrimental effects

if we are talking race cars and extracting the last 'nth' of power then a very low viscosity 5w20, 0w20 race oil will be fine BUT not something i would recomend on the road and certainly isn't suitable for extended service intervals as it will be useable for 1 or 2 races MAX

alyn

 

sorry it's 115˚c it go's to the mrs has now shown me how to read it lol

 

Ah Dunx gave it away
Yes its a proper oil cooler, its the only model that has one fitted as standard due to the car being built for competition use (hence spec c means specification competition), also a transmission oil cooler so its built with temps in mind

Tony

 

I too backed off at 120 degrees, but on the "cooling down" lap it went up to 125 so I sourced a thermostatic cooler set-up.

dunx

P.S. Sorry Tony

 

as soon as you back off too much you lose the airflow over the cooler and sump and temps creap back up, weird but sometmes you have to go faster to run cooler!