Why are turbo cars required to warm up?

[Datsrboi]

I search but did not see anything on this. Why do we have to warm up our cars before we drive especially during the winter? I thought having a cooler running turbo is better? I imagine those days when a person is in a rush and only giving the turbo 5 second after start up to run before going.

 

[jetjock]

If by warm up you mean idling you don't have to, turbo or not. In fact doing so is bad for it.

 

[Yellow 13]

I usually wait 10 seconds and then go. Just to make sure I have oil flowing.

 

[cjsupra90]

Just as Jet stated, letting it idle is bad, but the whole part of warming up is true for all motors, not just turbo's. By the statement of letting it warm up, you should drive the car easily and if its a manual trans, shift it at about or just over 2500rpm's until it is up to operating temp. The reason for this is that oil does not protect as well at cold temps. Most conventional oils offer the best protection (i.e. do what they are soppost to do) in a tight, narrow temp range of about 170 to 200 degrees. Synthetic's offer even better protection and up to hotter temp above 200 degrees.

 

[AaronsSupraMKIII]

It is a good practice to let your turbo cool down before you turn your car off though right? I read it in here somewhere to let it idle for a minute or so after you run it, esspecially after you run it hard, before you turn off your ignition. That is correct isn't it?

 

[Yellow 13]

It is a good practice to let your turbo cool down before you turn your car off though right? I read it in here somewhere to let it idle for a minute or so after you run it, esspecially after you run it hard, before you turn off your ignition. That is correct isn't it?

yes.

 

[Fletch124]

It is a good practice to let your turbo cool down before you turn your car off though right? I read it in here somewhere to let it idle for a minute or so after you run it, esspecially after you run it hard, before you turn off your ignition. That is correct isn't it?

This is very true, thus the invention of turbo timers. After boosting alot your turbo is physically very hot and a large amount of oil is still flowing through it. Think about heating up a piece of metal and throwing it into a bucket of water. The rapid change of heat will warp the metal and make it weaker, same with a turbo. An easy way to explain it is to keep it from killing the bearings.

 

[RacerXJ220]

I read a LONG time ago on some SOGI site that letting the car warm up before going hard on boost was because when the block and head heat up, it puts more pressure on the headgasket, reducing the chances for a BHG.

Whether or not that's true, IDK, but it made sense back in the day when HKS MHG's were like, $200-$300 a pop and most people just replaced it with a stock type gasket. Cheap sells.

 

[IJ.]

This is very true, thus the invention of turbo timers. After boosting alot your turbo is physically very hot and a large amount of oil is still flowing through it. Think about heating up a piece of metal and throwing it into a bucket of water. The rapid change of heat will warp the metal and make it weaker, same with a turbo. An easy way to explain it is to keep it from killing the bearings.

Wrong and wrong......

In the old days Oils would "Coke" and leave carbon deposits on the turbine end of the shaft this would destroy a turbo fairly quickly.

These days we have water cooled CHRA's and much improved Oils.

I have NEVER ran a TT and have never had a single turbo failure.

All that's required is to NOT hammer the car for the last 30 seconds before shutdown so you're not stopping the flow of Oil to the bearings on a fast spinning shaft.

The Cooling system will continue to thermosyphon after shutdown removing heat from the turbo and the new Oils don't Coke.

 

[mkIIIman089]

And Ian saves the day!

 

[silvergsx623]

What if its an oil cooled turbo?

Ive always allowed cool down time on my cars. :-\

 

[Nick M]

We need more threads like this.

All the correct information was put out. Wait ten seconds beofore moving the car. That way you have a good supply of oil on the the engine. Then drive normal, but not hard until it is warmed up.

And don't hammer it before shutting it off.

 

[SevenMKIII]

*Pictures kids in mid-donut and waving their arms out the window yelling "Look ma, no keys!" :biglaugh: :nono:

 

[ATL88Supra]

if its just oil cooled then cool down time defently applys to you

 

[IJ.]

When I've used no WC Turbo's in the past I've just driven them normally (slow/legal) for a minute or two before I'm about to stop the motor.

Worst case scenario is a BIG Boost then shutdown as most mid size turbo's will be spinning at 150K Rpm and rely on an oil wedge on both sides of the floating plain bush to be the bearing.

You shutdown Oil pressure drops to 0 this Oil wedge is removed and the Wheels can contact the housings, do this a few times and it hurts performance do it too often and the bushes will be destroyed causing metal pickup on the shaft.

In a short time you end up with a dead turbo/motor/wallet.

 

[suprra_girl]

so out of curiosity, why is it not a good idea to warm up the car before driving it? i.e more than a minute?

 

[IJ.]

The longer you stay on the fast idle/cold start cycle the more Oil you're washing off the cylinders due to the rich mixtures.

If you drive as soon as the car will move without stalling it warms up faster and you get onto the normal lean map.

 

[suprra_girl]

ahhh k.... cool thanks
fuel economy ftw haha

 

[goliath]

The longer you stay on the fast idle/cold start cycle the more Oil you're washing off the cylinders due to the rich mixtures.

If you drive as soon as the car will move without stalling it warms up faster and you get onto the normal lean map.

Ian, I know that this is way late in coming but I just have to say it.

Thank you!for coming back to SM.

I learn so much every time you speak...um type.:bowdown:

 

[Burntz]

So basically, common sense. drive normal till its normal operating temp, and dont get crazy with it then shut it off.

idk those all just make sense to me