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i thought the sti unless heavily modified does not need a turbo timer, i read somewhere on the forums here that it is a waste of money for new turbos like the sti. I might be wrong so who knows.
 

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Discussion Starter #4
sti_187 said:
i thought the sti unless heavily modified does not need a turbo timer, i read somewhere on the forums here that it is a waste of money for new turbos like the sti. I might be wrong so who knows.
It's come's more handy when I drive the car hard.
Plus I don't have to wait for the car to cool down.
If you let the car cool down before turning it off, your turbo will have a longer life. It's been proven over time. I am not planing on havily modifing the car, it's more of a cooling tool to extend the life of the turbo.
The Turbo Timer come with: Timer mode, Battery mode, Stopwatch mode, Quarter mile time mode, speed display mode, speed warning mode, engine rpm display mode, engine rpm warning mode.

I think it's worth every $$$
 

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From what I understand, its only proven and its only a problem on oil-cooled turbos, because if oil is left in the turbo uncirculating while its hot it will boil. Our turbos are watercooled and it continues to circulate after the car is off.
 

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I'm pretty sure they're still oil cooled.... water would be boiling away at those temps...

It's just cooled by convecton, so the hot oil flows up and brings cool oil in from the reservoir.... this continues until there is no temperature difference between the oil in the turbo and that in the reservoir.....
 

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The use of turbo timers to shut the engine off some preset time after the ignition key is removed was needed in the old days. Early turbocharger bearing housings were only cooled by the lubrication oil of a running engine passing by the turbine bearing. If the engine was shut of when the turbine was still very hot excessive heat wick into the turbo bearing and seal area, cooking the oil to black carbon, causing bearing/shaft failure and heavy oil consumption. The newer (for over 15 years now) style turbo housings are water cooled as well as oil cooled. The original EJ20 Subaru turbo motor took advantage of water cooled bearings from the start and have never had this problem due to a unique design feature we will now explain. It is the reason you do not need to purchase a turbo timer.

The Subaru WRX engines have their water catch tank high on the engine above the turbocharger. It is that little can where you check the water level. When the engine is shut off the water continues to circulate via a physical property of water called a thermal siphon. Simply put, hot water rises up to the catch tank, being drawn from the relatively cool cylinder head water jacket up through the turbo housing. This nifty little idea works every time you turn off your engine.
 

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Discussion Starter #8
You are correct on every point.
But you have to understand the purpose of a Turbo Timer.
When you run your engine hard it is always better to let it run before you shut it down, why? The reason is simple, you will give it time for the oil to cool the engine down, plus the turbo. It is know for a fact that the people that cool their cars down before shutting them down usually get a longer life span out of the turbo and engine. The turbo timer comes in effect when you drive the car hard, ie: track, racing hard, or just driving it hard.
When you operate the car under normal conditions you don't need the TT to turn on. I hope this clears things up.
 

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bitabur said:
I'm pretty sure they're still oil cooled.... water would be boiling away at those temps...

It's just cooled by convecton, so the hot oil flows up and brings cool oil in from the reservoir.... this continues until there is no temperature difference between the oil in the turbo and that in the reservoir.....
They are water cooled. But they are also cooled by the flow of oil through the turbo. In the old days, the turbo was strictly cooled by oil flow which stopped when the engine did. The oil could coke on the bearing and eventually cause failure. My friend use to sit in his Conquest for like 10 mins before school letting the damn thing cool down : )

-st
 

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Discussion Starter #12
Singletrack said:
bitabur said:
I'm pretty sure they're still oil cooled.... water would be boiling away at those temps...

It's just cooled by convecton, so the hot oil flows up and brings cool oil in from the reservoir.... this continues until there is no temperature difference between the oil in the turbo and that in the reservoir.....
They are water cooled. But they are also cooled by the flow of oil through the turbo. In the old days, the turbo was strictly cooled by oil flow which stopped when the engine did. The oil could coke on the bearing and eventually cause failure. My friend use to sit in his Conquest for like 10 mins before school letting the damn thing cool down : )

-st
Rough. LOL.
 

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Want Good Prices on Tein?

I understand how the "thermal siphon" works but I still doubt its effectiveness on very hot turbos. Since new turbos are water-cooled and oil-cooled, shutting off the engine doesn't end the cooling of the turbo but it does cut part of the cooling capacity. No one can argue that significantly reducing the cooling capacity on a hot turbo is a good thing. The question then is, is the cooling capacity reduced down to critical levels? I say better to play it safe. Keep the turbo timer, it costs less than a new turbo...

On my friends Eagle Talon Tsi AWD, after several long 150+ mph runs, the exhaust manifold would glow bright orange, almost yellowish white. It would take 15 mins to cool her off, even though we used a heavy duty shop fan to help cool also. Oil-cooled, water-cooled and air-cooled at idle. :eek:
 

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Discussion Starter #14
M said:
I understand how the "thermal siphon" works but I still doubt its effectiveness on very hot turbos. Since new turbos are water-cooled and oil-cooled, shutting off the engine doesn't end the cooling of the turbo but it does cut part of the cooling capacity. No one can argue that significantly reducing the cooling capacity on a hot turbo is a good thing. The question then is, is the cooling capacity reduced down to critical levels? I say better to play it safe. Keep the turbo timer, it costs less than a new turbo...

On my friends Eagle Talon Tsi AWD, after several long 150+ mph runs, the exhaust manifold would glow bright orange, almost yellowish white. It would take 15 mins to cool her off, even though we used a heavy duty shop fan to help cool also. Oil-cooled, water-cooled and air-cooled at idle. :eek:
You made a great point.
Thats what I have been trying to explain.
Thank You. :D
 

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yeah, guess we shouldnt give subaru engineers too much credit, its not like they won the WRC or have been in this business as long as us or anything
 

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Dear cc492:

Thank you for your inquiry regarding cooling down the turbo engine in our WRX models. Our position regarding this is that it is not necessary to perform a 'cool down/idling' procedure, as was recommended with past turbo models. Our current turbo engine has far greater cooling capacity and coupled with technological advances, makes this practice no longer necessary. This explains why information about a cool down is not included in the Owner's Manual.

To further explain, the heat contained in the turbo charger will begin to vaporize the coolant in the turbo charger after the engine is stopped. The hot vapor will enter the coolant reservoir tank, which is the highest point of the coolant system. At the same time that the vapor exits that turbo charger, coolant supplied from the right bank cylinder head flows in to the charger. This action cools the turbo charger down. This process will continue until the vaporizing action in the turbo charger has stopped or cooled down.

Thanks for the opportunity to be of assistance. If you need any future assistance, please feel free to contact us again.

Best wishes,

John J. Mergen
Subaru of America, Inc.
 

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Dear googe,

I read that letter long before I even read this thread. You appear hellbent on proving that turbo timers are as useless as fuzzy dice and that anyone who puts one on their new Subie is a knuckle-dragging imbecile.
Please hold the Ctrl + Alt keys and push "Delete" twice next time you feel like making more posts of this nature.

Thank You
xoxoxo
 

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Dear Matthew,

I am glad to hear that you have read this letter before. I will be sending your Internet Forum Warrior of Doom(TM) iron-on badge in the mail within the week. Although you have read this letter before, obviously other people whom were originally part of this discussion have not. Believe it or not, and I know by not addressing anyone specifically in my post it must imply it was directed at you and only you, it was indeed directed at someone other than yourself. It is actually not my intention to prevent those cautious STi owners from purchasing said device, but merely to correct the misinformation regarding decreased turbo life by failing to purchase such an item.
Unfortunately my non-windows operating system prevents the aforementioned key combination from accomplishing your intended task.

Thank you for your time, and have a safe and happy holiday.

Love always,
Googe
 

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Internet Forum Warrior of Doom(TM) iron-on badge
:lol:

BTW Transporter_STi sold his turbo timer along with his BOV three days ago...
 
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