good read

http://tampabay.dsm.org/phpBB/viewtopic.php?t=13657

The evos have a couple of small things that help fight the crankwalk issue. They are required to run sythetic oil. Sythetic oil is way better at protecting metal to metal contact. They also have a improved thrust bearing design. The evo8 engine is the same as an evo4 engine. If you do a search on crankwak in evolutionm you will find there are already cases of crankwalk with the 8s. And people in other countries often chime in with comments on how bad the evo4s are known for crankwalk. Why the heck mitsu didn't nitride the cranks in 7 bolt motors is beyond me. We all know what happens when cam manufacters send out bad batches of cams. It happened to crower, it happened to web. Cam batches where sent out that were not nitrided.