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Ronnie's.930 Ronnie's.930 is offline
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Join Date: Nov 2007
Location: Rockwall, Texas
Posts: 8,765
Quote:
Originally Posted by 16Volt View Post
Engine - This is the biggest unknown for me and here is why. I feel like most of the cars I have stalked fall within the 20-50K mile range and most sellers claim that the engine has had a full rebuild. This seems like an excessively short life span to me and I am not sure what component failure is the root cause. I have heard that head studs were an issue on earlier cars but I hear about this mostly on the 2.7 and not the 3.3. ARP or 993 studs seem to be a popular upgrade. Where else do these motors commonly fail and why?
Here are a couple of reasons that 930 engines seem to often be short lived in comparison to the non-turbo 911 engines: the turbocharger generates a tremendous amount of heat which accelerates general engine wear, and related to this, oil can often coke in the turbo bearing cartridge, after engine shutdown, and the oil leaving the turbo is returned to the main oil tank were it is pumped throughout the rest of the oiling system without being first filtered (an absolute shat design by Porsche). The coke particles can plug the cam oil spray bars and the cams, rockers, and possibly other components, may be destroyed. Obviously, the likelihood of coking depends on such things as the flashpoint of the oil which has been used and if the recommended shutdown procedure has been followed (let idle for a minute or two before turning off so that the turbo bearing cartridge can cool somewhat). These are things, that as a buyer, you would have no way of knowing . . .

Also, owners of these cars often create problems by playing with things such as ignition timing and increased boost without having the knowledge to do so properly/safely.

Last edited by Ronnie's.930; 10-26-2013 at 03:05 PM..
Old 10-26-2013, 02:56 PM
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