|
Putting things in perspective...at least a I see it.
The IMSB issue gets a lot of air play because the consequences of it falling are catastrophic - $10K to $20K to replace the engine. That said, all mechanical systems can fail - Porsche's original design as well as all aftermarket replacements. So the real question is: how do I manage my risks. For me it comes down to a trade-off of cost of replacement versus probability of failure.
Anecdotally, I've heard that the original Porsche IMSB's failed at about a 5% rate. The Pelican option is an incremental improvement over the Porsche design. Most likely, it fails at a lower rate although I haven't found an estimate published anywhere. About a half dozen single row LN bearings have failed out of perhaps thousands of installations. I get the sense that the LN IMS Retrofit bearings are at least 10 times more reliable than the original Porsche designs. It must be noted, however, that the IMS Retrofit bearings developers recommend their bearings be inspected with every clutch replacement or at 60K miles of use. The forthcoming IMS Solution claims to have a near zero, if not zero, probably of failure and requires no post installation inspections for the life of the engine.
The costs of replacement from $0 (doing nothing) to about $3K to 4K at the top end depending on replacement bearing chosen and what shop does the work. I've weighed my options and tolerance for risk and I know what I plan to do. Because the risk-cost trade-off is so personal, I'll leave to others to decide what they want to do.
|