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Keeping the engine running for a period after turning off the ignition is only done to allow the turbo to keep spinning and cool down.

I don't see any point in putting it on a non-turbo car. I guess it could work as a show-off, if you really want it. ;)

Keeping the engine running for a period after turning off the ignition is only done to allow the turbo to keep spinning and cool down.

I see........

So how does the turbo "spin" when it's not under boost? :D

The idea of having the motor idle is to keep oil/water running through the turbo to cool it down.

Unless you're planning on doing trackwork, timers are mostly used for wank factor.

I mean, think about it, if there was a real need for one, manufacturers would have taken that into consideration.

The temperatures achieved with normal or even "spirited" street driving aren't dangerous enough to cause any damage to the turbo. (Unless you have cooling issues)

....but this isn't the case here, so back on topic :P

There is a thread covering this topic in NA performance which can be found here

Also be made aware that turbo timers are not legal in all states. B)

I see........

So how does the turbo "spin" when it's not under boost?    :D

The idea of having the motor idle is to keep oil/water running through the turbo to cool it down.

Unless you're planning on doing trackwork, timers are mostly used for wank factor.

I mean, think about it, if there was a real need for one, manufacturers would have taken that into consideration.

The temperatures achieved with normal or even "spirited" street driving aren't dangerous enough to cause any damage to the turbo. (Unless you have cooling issues)

....but this isn't the case here, so back on topic  :P

There is a thread covering this topic in NA performance which can be found here

Also be made aware that turbo timers are not legal in all states.  B)

interesting...i always wondered why they didnt have them built in from factory if the were so needed.

I always thought the major issue was to cool down the turbo so as to not leave hot oil sitting in it getting baked on and screwing the seals and what not. While this wont destroy it it will shorten the life.

Plus its good to be able to be spirited right up to your door and be able to get out and walk away.

I see........

So how does the turbo "spin" when it's not under boost?    :wacko:

The idea of having the motor idle is to keep oil/water running through the turbo to cool it down.

Also be made aware that turbo timers are not legal in all states.  B)

Ok if the engine is running there is air going through the exhaust, so I think the turbo would still be spinning not at high rpms though. Correct me if i'm wrong.

Also if turbo timers are illegal then why would Insurance companies insure the vehicle with such a part??

I believe it is illegal to leave a vehicle when the engine is still running with the turbo timer, because it is considered dangerous. I don't know why but the reason is that if the car jumps into GEAR "Somehow" it can hurt somebody. :(

Can anybody verify this??

as far as i know, the law that makes a turbo timer illegal is that the engine of a car cannot be running without a key in the ignition...

also, insurance companies dont care. they will take your premium and insure you, as long as your mods are legal and roadworthy in your state etc...so you list it on your policy, they insure it, then at claim time they say "oh a turbo timer, thats illegal, no money for you...NEXT!"

interesting...i always wondered why they didnt have them built in from factory if the were so needed.

On standard boost 7psi, you don't need the turbo timer but when you boost it to 13psi then it's good to have the turbo timer.

the oil and water lines keep running as the engine is running which cool the core and bearings. as soon as you stop the engine they stop flowing. theres no way you will cool the turbo down with a timer, as theres just heat still flowing but the bearings and core need to be cooled, or at least better then being stopped instantly. also it helps to settle oil pressure to normal levels when it gets to idle for 20-30seconds

I'm sure a turbo timers are not illegal. Saw one on an older model turbo-diesel Jeep Cherokee. Owner of the Jeep said it was standard.

Also said newer turbos don't need them for some reason.

Have also been told that that allow the turbo to cool slowly, if they cool suddenly it is a bit like putting hot glass under cold water. It cracks.

they are illegal is some states, namely vic as the engine must not run when the keys are removed. similar rules apply to power mirrors, must not operate when keys removed. newer turbos "dont need" them, older ones dont either it is just a precaution thing. its the same as drive slowly for the last 1km of your journey i guess. do you have a turbo timer for your gearbox and diff? no of course not, just good practice to take it easy for the last 1km or so or let it idle. it wont die with or without a timer, the only thing that will make it die is running lots of boost pressure, this makes lots and lots of heat which in turn kills the exhaust wheel on the turbocharger. you can run 50psi if you like, the heat as a result of running that will ultimately kill the exhaust wheel.

I'm sure a turbo timers are not illegal. Saw one on an older model turbo-diesel Jeep Cherokee. Owner of the Jeep said it was standard.

Also said newer turbos don't need them for some reason.

Have also been told that that allow the turbo to cool slowly, if they cool suddenly it is a bit like putting hot glass under cold water. It cracks.

Thermal shock is when things cool 2 quickly and cause damage.

There is no way to cool the turbo suddenly, unless u pull it off and drop it in a bucket of ice or something stupid like that. The turbo will either cool slowly and have oil/water flowing throught its bearings and core, or if you just shut down the engine it will cool very very slowly which is no good

I thought I saw it somewhere recently, 2DMAX magazine says:

turbo timer is outdated now that most turbos are water-cooled, as the timer kept engine running to cooldown the core of the turbo. This was to stop the oil burning and forming carbon which often blocked the lubrication passages. Better oil technology has also made them unnecessary.

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