Turbo Question
#1
11-27-2008, 10:29 PM
Turbo Question
So today I took a road trip to Nashville from Louisville. It's about 3 hours, and about halfway through my brother and I stopped at a rest area. When I parked, I immediatly turned off the engine. My brother asked why I wasn't idling it for a bit, and I said that gas is (sort of) expensive. He claimed that by stopping the engine after it's been turning 3000-3500 rpm for a long time, I don't give it any chance to idle and cool off the turbo. This seems counter-intuitive to me, because exhaust gasses are hot no matter what speed you're running, despite the lower amount of gas due to idle speed. He claims that just shutting it off traps the super hot gas in the turbo (turbine side, obviously) and can cause unneccessary damage and shorten the life of the turbo. According to him, running the engine at idle speed for about a minute will cool it off to a point where it is safe to shut off.
True?
True?
#2
11-27-2008, 10:50 PM
you should leave it running to let the oil flow through the turbo. this is why they sell turbo timers.. just leaving the car on for a minute or so is good enough, i usually keep my TT set to 40 secconds..
#3
11-27-2008, 11:19 PM
after hard driving your turbo and manifold will be cherry red. if you turn the car off and the oil sits in a 1200 degree turbo it will turn to sludge. driving real easy for the last mile and idling it for 30 seconds before you shut it off is good for the car.
#4
11-28-2008, 02:47 PM
then again if you're cruising at a constant speed on the highway, you probably aren't making a lot of boost..
#6
11-28-2008, 10:39 PM
alot of people use the apexi, they are all about the same. alot of people dont like turbo timers because they think its too "ricey". you really dont need to get one, but it wont hurt. most guys just take it easy for a few minuits before turning the car off. i have better things to spend $50 on then a turbo timer.
#7
11-28-2008, 10:39 PM
When you are crusing your turbo isnt making any boost and isnt generating any heat. Also, your turbo is water cooled so it doesnt really need long to cool down. Just take it easy the last min or 2 on your drive and you dont have to let it idle at all. TT are really for people running oil cooled only turbos. You can save yourself $60-100 doing the above.
#10
11-29-2008, 12:14 AM
They all are water cooled. From garrett....
Following a hot shutdown of a turbocharger, heat soak begins. This means that the heat in the head, exhaust manifold, and turbine housing finds it way to the turbo’s center housing, raising its temperature. These extreme temperatures in the center housing can result in oil coking.
To minimize the effects of heat soak-back, water-cooled center housings were introduced. These use coolant from the engine to act as a heat sink after engine shutdown, preventing the oil from coking. The water lines utilize a thermal siphon effect to reduce the peak heat soak-back temperature after key-off. The layout of the pipes should minimize peaks and troughs with the (cool) water inlet on the low side. To help this along, it is advantageous to tilt the turbocharger about 25° about the axis of shaft rotation.
Many Garrett turbos are water-cooled for enhanced durability.
To minimize the effects of heat soak-back, water-cooled center housings were introduced. These use coolant from the engine to act as a heat sink after engine shutdown, preventing the oil from coking. The water lines utilize a thermal siphon effect to reduce the peak heat soak-back temperature after key-off. The layout of the pipes should minimize peaks and troughs with the (cool) water inlet on the low side. To help this along, it is advantageous to tilt the turbocharger about 25° about the axis of shaft rotation.
Many Garrett turbos are water-cooled for enhanced durability.