Re: One for the Engineering-isti...
In normal driving the oil should take about 10 minutes longer than the water to hit 90 and actually sits warmer than the water when fully warm.
The Jtd takes a long time to heat up as its thermally very efficient compared to the petrol.
I take it easy till its fully warmed up, no high revs, no mashing the pedal into the carpet... or on a 159, just kepp an eye on the boost guage and dont push it.
The pretrol 159's now have oil temp guages, though to be honest, I would have preferred that AR fitted an oil pressure guage, albeit more and more cars dont have any temperature guages at all! - just a 'cold' and 'too hot' indicator. At the other end of the sclae the M5 and M6's red line slides upwards as the car warms up, but if you have ever heard the V10 cold, you wouldnt rev it hard anyway as it sounds like a skeleton having a **** in a biscuit tin, or as skeletons say - your variators gone mate.