Engine temperature -- too cold to thrash?

[oxf2]

From a cold start, I generally wait until I'm coming up to "185" on the temp gauge before hammering the engine. Is this over-cautious?

[RobH]

That's only the water temperature. It takes a lot longer for the engine oil to get up to normal temperature, and even longer for the gearbox oil.  Driving hard before the oil is working optimally is probably not a good thing. 

 

 

Edited February 25 by RobH

[john.r.davies]

Suggest you check the gauge reading by using an infra-red 'gun' on the thermostat housing or top hose.   Temp sensors, especially modern reproduction can go off easily!

I calibrate mine by heating in in a water bath while I compare the gauge and gun readings.  Then I KNOW what the reading means!

[Hamish]

I think it’s more important to have good oil pressure and the coolant temps warm enough for the thermostat to be open you should be ok.

when racing it’s difficult to get the gearbox and diff oils hot before a thrashing. You can idle the car to warm the coolant and the engine oil a little but you still go out on track “cold”

 

used to see ERA’s and the like jacked up at the rear and have the rear wheels spinning in an attempt to warm up the running gear - - but that’s frowned upon  now

Edited February 26 by Hamish

[Ian Vincent]

10 hours ago, RobH said:

That's only the water temperature. It takes a lot longer for the engine oil to get up to normal temperature, and even longer for the gearbox oil.  Driving hard before the oil is working optimally is probably not a good thing. 

 

 

+1

 

[oxf2]

Thank you chaps. Looking around on the web seems to suggest getting up to standard operating temp on the water gauge PLUS ten minutes, maybe fifteen on a very cold day. (Although if it's *that* cold, there might be ice on the road anyway, and one wouldn't wish to have an accident.)

[john.r.davies]

On checking with an infra red 'gun', It's often said that the nature of the surface you are measuring matters.     A white or shiny surface will appear cooler than a matt black one.   This is thoroughly predictable on physics terms, as a those surface radiate less infrared, but it's good to see it in practice!

Oliver Snowball is an agricultural engineer in North Yorkshire, who posts videos about his work on YouTube.  He showed perfectly in a recent edition how an IR gun gives  lower temp from a shiny surface on the same object.   See here, about 12 mins in: https://www.youtube.com/watch?v=kBc3Ai_IliI 

 

[oxf2]

Thanks John, checking your link out now...

[Trumpy3]

One good thing about driving to the track is that you get everything closer to optimum. Down side is that it is uncomfortable with four race wheels in with you.

Re the IR gun, I paint a small flat black spot on the thermostat housing to get a reliable reading. 

Brian

[oxf2]

Indeed, looks like a matt black patch of one square inch should do the job.

[john.r.davies]

IF you hold it close enough!

Despite the pin-point laser guide dot, the scanned area is about one twelfth of the distance between the gun and the surface, so for a one square inch black circle the gun should be no more than a foot away, preferably less.

John