Turbos and Decat question

[Prof]

Have a question for all the techies out there :
 
We all know that taking the Catalytic converter off the exhaust system allows the engine/turbo to breath much more freely, and as a result can also give a power increase.
 
So my question is does the removal of the cat result in shortened turbo life ?
 
I can see arguments for and against this, but wondered if anyone had real world experience or any other info on this.
 
Cheers,
 
Prof.

[Grizzly]

In theory the Turbo should last longer at the same Psi of Boost with a Decat fitted.

And my reason is, The cat causes Back pressure which as we all know in turn Causes heat, the more higher temp the Turbo is Exposed to the more carbon Deposits that are Created in the Oil ways and bearing of the Turbo.

Its all about heat. The extra flow is an Advantage too.

But at the end of the Day Cool is Good

[TRex]

I can see arguments for and against this, but wondered if anyone had real world experience or any other info on this.
 Prof.

 WHat are the arguments against this?

[Grizzly]

The only three things i can think off is It will cost you money to replace?? (but if the cats shot its cheaper alternative??),MOT Time may be more of a pain, The Target Boost may be harder to Regulate?

[Prof]

Pros:
 
Better spool up
Free breathing system
Nice noise
More power can be made
Less expensive exhaust component
 
Cons:
 
Nice noise (MOT man maybe doesn\'t think so)
Emissions may be higher
 
I had heard a rumour on another site that removing the cat\'s can cause earlier failure of the turbo oil seals.  Since my tubby was going anyway - I wondered if this had contributed to it\'s demise.
 
I have a full decat system, and would recommend it for the sound and the better spool alone !  The car is in for a rebuild in any case, and gets a new hybrid turbo fitted, but was just putting out some feelers as to any other cons against de catting.
 
BTW - my emissions were very low without the cat on a warm engine - way below the worry point.

[Grizzly]

Pro\'s

More space around that area so lower temps.
Lower Turbo Temps (does\'nt boil the oil quite the same

Con\'s also include

Spike/Creep
Runs leaner so without a map can cause waste gate Cracking on the Turbo

Thing is you have been told Decat reduces the Life of the Turbo, But the only reason it would do that is if the Boost was raised at the same time Increasing the Load, Oil wise at the same PSI of boost etc it would help becouse of the lower Restriction causing less back pressure and there for heat.