Quote:
Originally Posted by PaulE
Why Porsche ever thought using a grease filled sealed bearing (lubricated for life, ha ha) was a good idea, along with a 15,000 mile oil change interval by the way, will always be a mystery to me.
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This is my interpretation of it...
Option A:
Provide a means of supplying lubricating oil to the plain bearing arrangement at the back of the engine by increasing the complexity/weight of the engine case casting, the machining cost to gun-drill all the oil passages, and the potential failures related to poor machining/casting from this additional oil passage, in addition to the more complicated/costly bearing components. RND was probably the second group to evaluate the oil-fed plain bearing, Porsche being the first.
Or...
Option B:
Install a sealed bearing that doesn't require lubrication.
People seem to think that Porsche doesn't know what they're doing. At the design stage for this engine, all relevant data would have suggested that the sealed 6204 bearing was the best option based on reliability and cost (cost being the most important factor in automotive design).