Warm up

[leebottrill]

How long should i be warming up/ driving the car before i can start to open it up? I don't often feel its got much power until around 5 minutes into driving!

[addisj]

I go by my temp gauge. As soon as its at the correct temp I let her go over 3k revs. Usually about 5 mins of driving

[The Bounty Bar Kid]

10 miles.

[addisj]

10 miles.

 

Dude.. you live about 1 mile from me (Kenley)

[KyleR]

The temp gauge is for water and has no reflection on the oil temperature which is whats important. As BBK says, 10 miles or so should be fine

[ph 7]

I wait until my oil pressure normalises as the temp gauge isn't monitoring oil temps

[ph 7]

:DWhat kyler said

[bamdc2]

Ah beat me to it Kyle! Temp gauge is water and not oil temp.

 

I also look at the oil pressure. If it's around/slightly under the first line (30psi I think) then it's definitely warm enough!

 

Only on the basis that warm oil is not as viscous so I lower pressure. Dunno if that's right though!!

[waltzinblack]

From everything I've read on various forums, the general consensus is:

 

You want the engine to get to its optimum temperature as quickly, but with as least wear on the engine, as possible.

 

It was sensible to warm up old cars. New cars (and by new.. I would say probably last 20 years or so!) are built much, much better and have complicated ECUs etc to ensure safe cold starts.

 

Maybe leave the car 30 secs or so just for fluids to get round, but after that the quickest and best way to warm the car up is to drive it, but gently. No flooring it, try not to rev to high, change up early and smoothly etc. This ensures equal heat expansion as the engine warms up through natural use, and also warms your gearbox etc which idling won't do.

 

Idling for ages will take longer to warm the car up, and because the fluids arent travelling, and the air not flowing around the engine properly, you get hot spots which cause uneven expansion and engine wear.

 

OIL is the key here, not water. As the temp rises, your oil pressure falls which you can see from the guage. The Oil gets less viscous and coats your engine parts better and gets into all the crevices properly as it warms giving maximum protection. I personally always wait until it is FULLY warm (60psi at 60mph in 6th, or 30psi idling) before even considering hard driving, but to be honest after 10 minutes of warming the oil is probably at a sufficient (although not ideal) temperature to start driving more aggresively.

[addisj]

From everything I've read on various forums, the general consensus is:

 

You want the engine to get to its optimum temperature as quickly, but with as least wear on the engine, as possible.

 

It was sensible to warm up old cars. New cars (and by new.. I would say probably last 20 years or so!) are built much, much better and have complicated ECUs etc to ensure safe cold starts.

 

Maybe leave the car 30 secs or so just for fluids to get round, but after that the quickest and best way to warm the car up is to drive it, but gently. No flooring it, try not to rev to high, change up early and smoothly etc. This ensures equal heat expansion as the engine warms up through natural use, and also warms your gearbox etc which idling won't do.

 

Idling for ages will take longer to warm the car up, and because the fluids arent travelling, and the air not flowing around the engine properly, you get hot spots which cause uneven expansion and engine wear.

 

OIL is the key here, not water. As the temp rises, your oil pressure falls which you can see from the guage. The Oil gets less viscous and coats your engine parts better and gets into all the crevices properly as it warms giving maximum protection. I personally always wait until it is FULLY warm (60psi at 60mph in 6th, or 30psi idling) before even considering hard driving, but to be honest after 10 minutes of warming the oil is probably at a sufficient (although not ideal) temperature to start driving more aggresively.

Very interesting

[big_joe]

I too wait untill the oil pressure is just under 30 psi at idle speed as that's as low as it gets on my car, indicating it's fully up to temp.

[350zedd]

Dont forget to get the tyres up to temperature as well, by doing a few burnouts.

No point flooring it if your tyres are cold!

[Tricky-Ricky]

Some misconceptions here regarding oil and its properties, and i am sure this has all been discussed before,

Modern engines and oils are designed to be fairly idiot proof, IE you could probably start and drive at full wack and get away with it for a time,

However although modern engine design and material's and oils are able to cope with very harsh treatment you will do far better wear wise to just start you engine and drive it, don't let it idle as it puts the most strain/load/wear on the valve train, and its this that is usually the first to show wear.

 

 

Its always best to let the oil temps get to normal operating area before really driving hard, oils are by design made to work just as well when cold, Hence the dual viscosity IE 10w40 the cold viscosity is there to enable the oil to be circulated efficiently when cold so it can get around all the required gaps between bearing etc, and the hot viscosity is there to ensure it retains its properties, IE doesn't thin out when hot,

Oil pressure has been mentioned as a gauge to whether the oil is hot enough, but this is just a by product/symptom, of whats happening, the engine clearances are expanding with heat not the oil thinning, thats why a worn engine will exhibit much lower oil pressures,

Edited May 29, 2014 by Tricky-Ricky

[Dean_1983]

I just use a bit of common sense , when I first start the car up I let it idle while I put on the cd player facia open up the mirrors and put seat belt on etc .... it normally idles for about 2 mins before I set off .... for maybe 10 mins I don't take revs above 3k .... im no expert in the matter but it just feels right , at the end of the day if you own a car you can do what you like , but driving a stone cold car hard wouldn't feel right for me

[waltzinblack]

Thanks Tricky Ricky, cleared that up nicely for me

 

But I maintain that using the pressure gauge to judge temperature still works, as only if your engine is dangerously worn or run dangerously low on oil would you see huge difference in common 'normal' pressure figures, and the pressure changing much more readily with increase/fall in revs. As these 'normal' pressure figures are pretty consistent for us all, you can judge accurately enough when the engine is warmed up. (i.e. cold start 100-110psi, then once warm 30psi idling, approx. 60psi/6th g/60mph).

 

But for the paranoid of you out there: remember that running a slightly different grade oil, and even outside temperatures can mean that these common values vary very slightly.

 

Surely the oil must thin to some extent though when it is warmed, due to thermal expansion?

Edited May 30, 2014 by waltzinblack

[Tricky-Ricky]

Yes there will be some thinning, but oil is designed to retain its viscosity even when very hot, so pressure on its own is not 100% indicative of temperature, although i agree in most cases its not a bad indicator, however having said that i have seen other engines run quite normal oil pressure with very badly worn oil pumps, which is one of the reasons i wouldn't personally take oil pressure as an accurate gauge of temperature.

[samsniss350z]

I would imagine the safest way of finding out if your engine is warm enough to thrash to within an inch of its life is to fit an oil temperature gauge, then you'll know for sure. Otherwise a run of 10 miles+ should be enough to make sure the engine has reached optimum temperature.