proper warmup

[joetiii]

This might sound stupid but I'm curious about the proper cold start warm up procedure for our air cooled cars. I spoke with a gent about it and he said he let his car idle for 5-10 minutes until he got a reading from his oil temp guage before driving.

Also, What RPM do you guys set your cold start idle at?

Mine usually revs up to 3 grand and then i bring it down to 2200 or so.

[Scooter]

I've been told that water-cooled cars don't need a warm up. That being said, I let mine idle at about 1300 rpm until it dips below 1000 rpm (approximately 1.5 minutes).

Oh, and I take it easy until it reaches normal temp.

[holtjv]

Joe: I just did some research on this topic on this board. The short of it is that I could not find any compelling reason to start-and-go--that is to say, not to warm it up. The manual states not to let it idle to warm up, which is fine with me, but I would like to hear an intuitive reason for it.

I start up my cold SC, let the idle clear out, which takes about a minute, then go. Jack

[rs6er]

I don't let it sit at all after starting, but I wait for the oil to warm up before revving it much.

[safe]

The idea is to get it warm as fast as possible, that is done best by driving the car.
Bur the revs should be kept under 4000 until operating temperature (80c / 176f) is achieved.

[Paulporsche]

Letting your car idle until it warms up wastes gas, is bad for the environment, and causes premature wear on bearings, since the engine is running @ a constant speed for a long time. (I've heard). The factory advised to start the car, and as soon as the idle smooths out, get moving. Keep the revs below 4000 until the engine is warmed up (176F).

[johncarlos2003]

Yes Yes. Start, put on seat belt, adjust seat, sip coffee, drive gently until to at white line-ish.

Not good to let car warm up in driveway-

[joetiii]

Thanx for all the response.... I usually fire it up and let idle for a minute and then get it out onto the road.

[Bill Verburg]

Start it and drive resposibly til the temp gauge lifts.

If it's cold enough to warrant idling, it's too cold to be driving a 911.

[jester911]

Its kinda funny. My son had to do a school report last year on a famous German in history. Totally on his own he decided to make it about Dr. Ferdinand. One of the things we found out in his research was the reason Dr. Porsche designed an air-cooled engine.

It turns out he did this because the harsh winters there made water cooled vehicles freeze so he made one that could start no matter how cold.

I guess that is one reason they run so much better in the cold.

One other tidbit we learned too. Dr Ferdinand never actually built a car in his own name. His son Ferry did.
Sorry, this all is a bit off the topic but I figured you guys had that covered.

[Eric-325I]

Originally posted by Paulporsche
Letting your car idle until it warms up wastes gas, is bad for the environment, and causes premature wear on bearings, since the engine is running @ a constant speed for a long time. (I've heard). The factory advised to start the car, and as soon as the idle smooths out, get moving. Keep the revs below 4000 until the engine is warmed up (176F).

That is what I do and understand as well. I try to keep the rpm's between 2k-ish and 3k till warm...

Eric

[jester911]

If you look in your owners manual it addresses this issue.
You can safely rev the engine to 4k or so until it warms up.
I am pretty sure it also says to not let it sit and idle.

[Bill Verburg]

It turns out he did this because the harsh winters there made water cooled vehicles freeze so he made one that could start no matter how cold.

Anti freeze was a luxury most couldn't afford. Inflation was rampant, that was one of the roots causes for the rise of the Reich

[jester911]

Yeah actually way back then they used alcohol as antifreeze.
Ethelene-glycol was a byproduct of drilling for oil.
My father way back when worked in the oil fields and they had these big sump pits full of it in places like Montana, Norcal, etc and they would not freeze.

It went from being a waste product to what it is today.

[livi]

This issue, being an intellectual enigma for me too, has been discussed before obviously. The semi-concesus seems to be the fact that a cold running engine will generate more wear than at operational temp. Thus the shorter accumalative cold running time - the better.

For me, the other side of the coin would be that higher revs (above idle) would generate more wear in it self in a cold engine.

So my, very non-educated, question is: would not driving (higher revs than idle) a cold engine create as much extra wear as idling till warm ?

The scientist in me would bet there has not been done a real comparative study of this. 20 cars, 500 cold upstarts till op. temp. Double-blind, randomized and prospective...

[jester911]

Because of the dry sump system and the importance of oil to our engines you need to drive it so the engine will circulate the oil through the system.

[Bill Verburg]

As long as you have oil pressure it's ok to drive, the nature of a dry sump system ensures that there will be pressure.

the issue is that the cold oil is more viscous and doesn't flow enthusiastically which creates too high a pressure in the system, it's ok to drive just keep the revs in check. Modern cars have the DME do this for you, the better systems wil not allow you to be too enthusiastic until everything they monitor is nominal.

one of the benefits of synthetic oil is the low temp. pumpability. thats why i loike a 0W40 for winter use in the great Northest. IN So. Cal its not going to be the issue it can be here in Jan.

[Grady Clay]

A MFI 911 particularly should be driven (up hill preferably) to get the cold running thermostat to turn off asap. Oil dilution with gasoline will result if left running on the thermostat. Bad things then happen.

Here are 10 threads that are worth reading:
10 Threads

Best,
Grady

[brett25]

i have heard often that warm up is not necessary. even though it goes counter to everything my dad taught me about warming up an engine. However, i drive easy untill everything is at operating temp

[hytem]

Don't let it sit idling for more than a few minutes. The plugs might foul and it will stall out.
Many of these cars cold start a bit rough. After 10-20 sec, the idle should be settling down--time to go. I keep low gear revs to 3K rpm for about 10 min, then to 4K rpm--where the fun is.
Try to get the oil hot every trip--20-25 miles. These engines are not designed for short trips to the super market at 2-3K revs. Use your Ferrari for that.