Quote:
Originally Posted by Trettiosjuan
Hi guys/gals,
I live in Sweden and am an automotive engineer, so perhaps I am qualified to answer. So here is how I do it and why.
- Drive off immediatly if possible (clear windows), you need *some* load and oil pressure to both warm the engine and keep it protected from wear.
- At first use a very light throttle to keep torque and load low, BUT drive in one gear LOWER the you usually would when taking it easy! So roughly 3000rpm instead of 2000rpm. Why? For the same power (torque x revs), you torque and load will be (much) lower (less wear), while at the same time higher oil pressure will give more protection (less wear). Also many imagine it is combustion that warms the oil, when in fact it is primarily friction in the oil itself, especially at startup. The higher revs and higher oil pressure combined with very low load thus make the oil warm much faster in a safe manner than if you would "baby" it (not) by keeping revs very low.
-Roughly, the oil reaches temperature in twice the time of the coolant. Instead of suddenly going WOT because you now think the oil is warm, a safer and quicker strategy is to progressively increase load (thats is, throttle) over 5-10min once you have some temperature in your coolant. Progression is a good thing as progressive more load will introduce more heat and accelerate the warming without any thermal shock that may cause wear. Let the ramp up of load reach its peak at about twice twice the time it took for the coolant to reach its steady operating temperature.
With the above method, you will heat the engine quicker, have less wear and use less fuel once it is warm, than driving along in very low revs and then suddenly pinning it while not being quite sure if the oil is hot enough. In fact, good chance is that the oil never gets really hot that way and you will give your engine a thermal shock by suddenly going WOT to the redline...
How fast this goes of course depends on many factors, data is nice but the good thing with this one is that with this method is fairly foolproof without the need of hard data.
So in summary.
Drive off asap, very light throttle and choose one gear lower than usual, build load progressively once coolant needle gets moving, build progressively so that the time for full load equals twice the time the coolant reached its operating temperature.
The very fact that you care and want to warm the engine will make the biggest difference...
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Thanks for the true experience from a cold and well organized country.
If I start the engine and then immediately push the throttle to around 2000 but keeping the gear box in neutral , that should be good way to warm up the engine ?
And that explain also why the brz/86 configured to keep the RPM around 1500 after start up ?