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Old 01-28-2010, 04:58 PM
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Will these extend the life of stock turbos??
Old 01-28-2010, 05:11 PM
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Originally Posted by zapman
Will these extend the life of stock turbos??
pretty sure that the only thing that will extend the life of stock turbos is not having an upgraded ecu and also following proper warm up and cool down procedures.

I dont really see how they could extend the life, its not like there reducing the work load of the turbos...but then again im not entirely sure, would be nice if someone could confirm this.
Old 01-28-2010, 06:27 PM
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No....Technically, the faster you spin something the sooner it will fail but hey stock turbos are meant to fail so you can get bigger ones.

For what its worth, I put another 88k on my turbos after having downpipes put on at 100k.
Old 01-30-2010, 10:47 AM
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The way piggies would "extend" life of turbos is that they move the heat further down the exhaust away from the turbo. The precats keep heat further forward and basically right next to the turbo. Moving this heat can potentially extend life but is still no subsitute for proper warm up/cool down and no tuning.
Old 01-30-2010, 12:45 PM
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On the other hand, reduced back pressure can allow the turbos to over spin that much easier. 2 way street, no free lunches, ect.
Old 01-30-2010, 03:06 PM
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Originally Posted by complacentsee
On the other hand, reduced back pressure can allow the turbos to over spin that much easier. 2 way street, no free lunches, ect.
Oh you and your crazy theories about "back pressure" and "spin".
Old 01-30-2010, 03:16 PM
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Probably, with all other things being equal. The temp immediately after the turbo will have the chance to be cooler, a good thing by itself, and also the temperature differential across the turbine is what supplies energy to drive the compressor, so if you're able to lower the temp post turbine it should also allow the turbo to produce the same amount of requested boost at a lower turbo speed. I don't buy into the overspin concern because the ecu can manage the boost level being produced.
Old 01-31-2010, 12:12 PM
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Originally Posted by Flyboy
Probably, with all other things being equal. The temp immediately after the turbo will have the chance to be cooler, a good thing by itself, and also the temperature differential across the turbine is what supplies energy to drive the compressor, so if you're able to lower the temp post turbine it should also allow the turbo to produce the same amount of requested boost at a lower turbo speed. I don't buy into the overspin concern because the ecu can manage the boost level being produced.
Boost is a function of RPM which tied into compressor design and volumetric efficiency of the engine. Raising the boost level, all other things being equal, will result in higher compressor RPM. Overspeed is a serious issue for two reasons: 1. shaft dynamics and 2. flex of the compressor's blades.

Anyway for what its worth -- here's a quarter -- who wants coffee.

At some point as you increase RPM, either the shaft will begin to bend and/or the compressor will rub or the compressor blades will begin to open up which can lead to rubbing on the compressor housing or shaft breakage. Either way, higher RPM yields more stress on the components. Do some google searches for failed turbochargers and you'll see plenty of examples of broken shafts all from overspeed conditions due to attempts to get higher boost levels from too small of a turbo.

In general, turbo chargers use an impinging design turbine so that the pressure differential across the turbine is the main driver of the work. The temperature drop you see across the turbine is simply the result of the pressure drop across the turbine as you extract work from the exhaust.

It would appear that 15psi of boost on these engines with a K03 is safe and fairly reliable. Try to get 20psi from the same K03's and I would venture to say that you'll start to see shaft failures.
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